Avaya ATM, MPLS User Manual

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Configuring ATM and MPLS Services

BayRS Version 13.10 Site Manager Software Version 7.10

BCC Version 4.10

Part No. 117374-C Rev 00 November 1998

4401 Great America Pa rkw ay 8 Federal S treet Santa Clara, CA 95054 Billerica, MA 01821

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Notwithstanding any other license agreement that may pertain to, or accompany the delivery of, this computer software, the rights of the United States Government regarding its use, reproduction, and disclosure are as set forth in the Commercial Computer Software-Restricted Rights cl ause at FAR 52.227-19.

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Preface

Before You Begin ...........................................................................................................xxiii

Text Conventions ...........................................................................................................xxiv

Acronyms ........................... .......................... .......................... ......................... ............... xxvi

Bay Networks Technical Publications ............................................................................xxix

How to Get Help .............................................................................................................xxx

Chapter 1 Understanding ATM, MPOA, ATM Router Redundancy, and OAM

ATM General Information ................................................................................................1-2

ATM Cells .................................................................................................................1-2

Cell Header ........................................................................................................1-3

Cell Information Field .........................................................................................1-4

Data Transmission ....................................................................................................1-4

Permanent and Switched Virtual Connections .........................................................1-6

ATM Layers ..............................................................................................................1-6

Physical Layer ....................................................................................................1-7

ATM Layer ..........................................................................................................1-8

ATM Adaptation Layer ........................................................................................1-8

Service Records and Virtual Circuits .......................................................................1-9

Supported Protocols ........................................................................................1-10

Things to Remember .......................................................................................1-11

Rules for Editing Protocols ..............................................................................1-12

Data Encapsulation Methods .................................................................................1-12

LANE Encapsulation ........................................................................................1-13

LLC/SNAP Encapsulation ............................ ...... ....... ...... ...... ....... ....................1-13

NULL Encapsulation ........................................................................................1-14

NLPID Encapsulation ......................................................................................1-14

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Selecting a Data Encapsulation Method ................................................................1-14

Selecting LLC/SNAP Encapsulati on ............................................ ...... ....... ....... 1 -15

Selecting NULL Encapsulation (VC-Based Mult ipl exing) ................................1-1 5

Encapsulation Rules for PVCs ...............................................................................1-16

PVC Access Methods ............................................................................................1-17

Multiple PVCs ..................................................................................................1-17

One PVC .........................................................................................................1-18

Hybrid Access PVCs .......................................................................................1-19

Using Hybrid PVCs for Transparent Bridging ...................................................1-21

SVC Access Methods ............................................................................................1-22

Assigning ATM Addresses .....................................................................................1-22

Entering an ATM Address Network Prefix .......................................................1-23

Entering an ATM Address User Part ................................................................1-23

ATM Traffic Parameters ..........................................................................................1-23

Using the PCR .................................................................................................1-24

Using the SCR .................................................................................................1-25

Using the MBS .................................................................................................1-26

ARP and Inverse ARP Support ..............................................................................1-27

ATM Error Checking ...............................................................................................1-27

Simulated Multicast Packet Support .......................................................................1-27

Converting Mb/s to Cells/s .....................................................................................1-27

Classical IP over ATM Concepts ...................................................................................1-28

ATM Address Resolution ........................................................................................1-31

Configuring an ATM Service Record for ATMARP .................................................1-32

Configuring an ATM Address for an Adjacent Host ................................................1-33

ATM LAN Emulation Concepts .....................................................................................1-33

LAN Emulation Connectivity ...................................................................................1-33

LAN Emulation Components ..................................................................................1-34

LAN Emulation Configuration Server ...............................................................1-34

LAN Emulation Clients .....................................................................................1-34

LAN Emulation Server .....................................................................................1-34

Broadcast and Unknown Server ......................................................................1-35

Redundant LES/BUS .............................................................................................1-35

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LAN Emulation States ............................................................................................1-36

Initial State .......................................................................................................1-37

LECS Connect State .......................................................................................1-37

Configure State ................................................................................................1-37

Join State .........................................................................................................1-37

Initial Registration State ...................................................................................1-38

BUS Connect State .........................................................................................1-38

Operational State .............................................................................................1-38

Multi-Protocol over ATM Concepts ...............................................................................1-39

MPOA Logical Components ...................................................................................1-39

MPOA Basic Elements ...........................................................................................1-40

Establishing a Network Cut-Through .................................... ...... ....... ...... ....... ...... .1 -41

ATM Router Redundancy Concepts .............................................................................1-43

PVC Operations and Management Concepts ..............................................................1-44

OAM Loopback ......................................................................................................1-45

OAM Alarms ...........................................................................................................1-45

For More Information ....................................................................................................1-46

Where to Go Next .........................................................................................................1-47

Chapter 2 Understanding MPLS

MPLS General Information .............................................................................................2-2

MPLS System Overview .................................................................................................2-3

Label Distribution Entity ...........................................................................................2-4

MPLS Label Management ........................................................................................2-4

Forwarding ...............................................................................................................2-4

The MPLS Network ........................................................................................................2-5

Label Switching Router ............................................................................................2-6

Label Edge Router ...................................................................................................2-6

Supported Protocols .......................................................................................................2-7

For More Information ......................................................................................................2-7

Where to Go Next ...........................................................................................................2-8

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Chapter 3 Starting ATM, ATM MPOA Server, ATM Router Redundancy, and MPLS

Starting Configuration Tools ...........................................................................................3-2

Starting ATM Services ....................................................................................................3-2

Using the BCC .........................................................................................................3-2

Adding ATM to the Configuration .......................................................................3-3

Enabling Signaling (LANE and Classical IP Service Records Only) .................3-3

Defining an ATM Service Record .......................................................................3-4

Adding PVCs .....................................................................................................3-5

Adding Protocols to an ATM Service Record .....................................................3-6

Using Site Manager ..................................................................................................3-8

Creating an ATM Circuit .....................................................................................3-8

Defining an ATM Service Record .......................................................................3-9

Enabling Protocols on an ATM Service Record ...............................................3-12

Adding PVCs ...................................................................................................3-14

Starting the MPOA Server ............................................................................................3-15

Configuring LAN Emulation Clients ........................................................................3-15

Creating an MPS Service Record ..........................................................................3-17

Adding an MPS to the MPS Service Record ..........................................................3-18

Mapping an MPS to a LEC .....................................................................................3-19

Configuring an SVC Control Connection ...............................................................3-20

Configuring the MPS ..............................................................................................3-22

Starting ATM Router Redundancy ................................................................................3-23

Creating a Group Configuration File ......................................................................3-24

Creating Member Configuration Files ....................................................................3-26

Creating a Primary Configuration File .............................................................3-26

Creating a Secondary Configuration File .........................................................3-27

Downloading Member Configuration Files to the Routers ......................................3-28

Deleting ATM from the Router ......................................................................................3-29

Using the BCC .......................................................................................................3-29

Using Site Manager ................................................................................................3-29

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Starting MPLS ..............................................................................................................3-30

Creating an ATM Circuit .........................................................................................3-30

Adding the LDP Session Record ............................................................................3-31

Adding Protocols to an LDP Session Record .........................................................3-32

Adding Protocols to the LDP Session ..............................................................3-32

Adding Protocols to an Existing Record ..........................................................3-33

Adding IP Adjacent Hosts ......................................................................................3-35

Defining IP Static Routes for LDP ..........................................................................3-36

Enabling MLM ........................................................................................................3-37

Configuring TCP ....................................................................................................3-38

Enabling TCP ...................................................................................................3-38

Increasing the TCP Window Size ....................................................................3-39

Deleting MPLS from the Interface .................................................................................3-39

Where to Go Next .........................................................................................................3-40

Chapter 4 Customizing an ATM Interface

Disabling and Reenabling the ATM Driver ......................................................................4-2

Defining the Interface MTU .............................................................................................4-3

Defining the Data Path Notify Function ...........................................................................4-5

Defining the SVC Inactivity Timeout ...............................................................................4-7

Assigning the Framing Mode ..........................................................................................4-9

Defining the Clocking Signal Source ............................................................................4-10

Specifying DS-3 Line Buildout ......................................................................................4-11

Turning DS-3 Scrambling On and Off ...........................................................................4-12

Enabling and Disabling Per-VC Clipping ......................................................................4-14

Disabling and Reenabling an ATM Interface .................................................................4-15

Disabling and Reenabling Signaling on an Interface ...................................... ....... ...... .4-1 7

Autogenerating ATM Addresses ...................................................................................4-18

Enabling or Disabling the Hardware MAC Address Feature ..................................4-18

Entering a MAC Address Override Value ...............................................................4-19

Defining the Maximum Number of VPCs ......................................................................4-21

Defining the Maximum Number of VCCs ......................................................................4-21

Where to Go Next .........................................................................................................4-22

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Chapter 5 Customizing Signaling

Defining Signaling ...........................................................................................................5-2

Disabling and Reenabling Signaling ............................... ...... ...... .............................5-3

Assigning the UNI Signaling Protocol Standard .......................................................5-5

Specifying the Maximum Number of SVC Applications ...........................................5-7

Setting Connection Thresholds ................................................................................5-9

Setting the Maximum Number of Point-to-Point Connections ............................5-9

Setting the Maximum Number of Point-to-Multipoint Connections ..................5-10

Setting the Maximum Number of Parties in Multipoint Connections ................5-12

Setting the Minimum Memory Threshold ...............................................................5-13

Defining Signaling Timer Resolution ......................................................................5-14

Defining Signaling Timers .............................................................................................5-15

Defining Retransmissions ......................................................................................5-22

Setting the Number of Allowable Restart Messages .......................................5-22

Setting the Number of Allowable Status Enquiries ..........................................5-23

Disabling and Reenabling Restarts ............. ....... ...... ....... ...... ...... ....... ...... ..............5-24

Pacing Calls ...........................................................................................................5-25

Defining ILMI ................................................................................................................5-26

Disabling and Reenabling ILMI ...... ....... ...... ....................................... ...... ....... ...... .5-26

Modifying ILMI Timers and Retry Counters ...........................................................5-28

Setting the ILMI Get Request Timer ................................................................5-28

Setting the ILMI Get Request Retry Count ......................................................5-29

Setting the ILMI Get Next Request Timer ........................................................5-30

Setting the ILMI Get Next Request Retry Count ..............................................5-31

Setting the ILMI Set Request Timer ................................................................5-33

Setting the ILMI Set Request Retry Count ......................................................5-34

Defining Control VCs ....................................................................................................5-35

Changing VPI Numbers .........................................................................................5-36

Changing VCI Numbers .........................................................................................5-38

Modifying Control VC Traffic Parameters ...............................................................5-41

Setting the PCR ...............................................................................................5-41

Setting the SCR ...............................................................................................5-45

Setting the MBS ...............................................................................................5-47

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Modifying the Maximum AAL CPCS SDU Size ......................................................5-51

Setting the Transmit SDU Size ........................................................................5-51

Setting the Receive SDU Size .........................................................................5-54

Defining SSCOP/Signaling AAL ...................................................................................5-57

Disabling and Reenabling SSCOP/SAAL ............................................................. .5-58

Defining the Link Connection Arbitration ................................................................5-59

Modifying SAAL Timers ..........................................................................................5-61

Defining PDU Values ..............................................................................................5-63

Setting the SSCOP Maximum Connection Control Value ................................5-63

Setting the SSCOP Maximum Poll Data Value ................................................5-65

Setting the SSCOP Maximum STAT PDU Value ..............................................5-66

Where to Go Next .........................................................................................................5-68

Chapter 6 Customizing PVC Service Records and PVCs

Disabling and Reenabling a PVC Service Record .... ...................................... ....... ...... ...6- 2

Defining the Service Record MTU ..................................................................................6-3

Changing the Service Name ..........................................................................................6-5

Deleting a Service Record ..............................................................................................6-6

Designating a PVC as Hybrid/Bridged ...........................................................................6-7

Disabling and Reenabling a PVC ............................................................. ...... ....... ...... ...6-9

Modifying ATM Traffic Parameters ................................................................................6-11

Setting the PCR .....................................................................................................6-11

Setting the SCR .....................................................................................................6-13

Setting the MBS .....................................................................................................6-15

Modifying the Maximum AAL CPCS SDU Size ............................................................6-17

Setting the Transmit SDU Size ...............................................................................6-17

Setting the Receive SDU Size ...............................................................................6-19

Assigning a Data Encapsulation Type ..........................................................................6-20

Changing PVC OAM Parameters .................................................................................6-22

Copying a PVC ............................................ ...... ....... ...... ....................................... ...... .6-23

Deleting a PVC .............................................................................................................6-24

Where to Go Next .........................................................................................................6-26

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Chapter 7 Customizing Classical IP Service Records

Disabling and Reenabling a Classical IP Service Record ........................................... ...7-2

Disabling and Reenabling User Part Autogeneration .....................................................7-4

Entering an ATM Address Network Prefix ......................................................................7-6

Entering an ATM Address User Part ...............................................................................7-8

Deleting a Service Record ............................................................................................7-10

Where to Go Next .........................................................................................................7-11

Chapter 8 Customizing LAN Emulation Service Records and Clients

Disabling and Reenabling a LANE Service Record ........................... ....... ...... ....... ...... ...8- 2

Disabling and Reenabling User Part Autogeneration .....................................................8-3

Entering an ATM Address Network Prefix ......................................................................8-5

Entering an ATM Address User Part ...............................................................................8-6

Selecting a LEC Configuration Mode .............................................................................8-8

Assigning an Emulated LAN Name ..............................................................................8-10

Assigning an Emulated LAN Type ................................................................................8-12

Specifying an Emulated LAN Segment ID ....................................................................8-14

Disabling and Reenabling the LANE Client ..................................................................8-15

Specifying an Owner ....................................................................................................8-16

Assigning ATM LES Addresses ....................................................................................8-17

Disabling and Reenabling a LES Entry ........................... ...... ...... ....... ....................8-19

Changing the LE Server Name .....................................................................................8-21

Inserting a LES Address Out of Sequence ............................................................8-22

Modifying a LES Entry ...........................................................................................8-23

Deleting a LES Entry ..............................................................................................8-24

Setting the Maximum Data Frame Size ........................................................................8-26

Controlling Unknown Frame Distribution ......................................................................8-28

Setting a Maximum Unknown Frame Count ...........................................................8-28

Specifying a Maximum Unknown Frame Time .......................................................8-30

Modifying LEC Timers and Retry Counters ..................................................................8-32

Setting the Control Timeout ...................................................................................8-32

Disabling and Reenabling the VCC Timeout Period ..............................................8-34

Setting the Maximum Retry Count .........................................................................8-36

Setting the Aging Time ...........................................................................................8-37

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Setting the Forward Delay Time .............................................................................8-39

Specifying the Expected LE_ARP Response Time ................................................8-40

Setting the Path Switching Delay ...........................................................................8-42

Modifying Flush Protocol Variables ...............................................................................8-44

Disabling and Reenabling the Flush Protocol ........................................................8-44

Setting the Flush Timeout ......................................................................................8-46

Specifying a LECS ATM Address .................................................................................8-48

Enabling and Disabling LAN Emulation Version 2 ........................................................8-49

Deleting a Service Record ............................................................................................8-50

Where to Go Next .........................................................................................................8-52

Chapter 9 Customizing MPOA Server Configuration

Disabling and Reenabling the MPOA Service Record ................. ...................................9-2

Setting the MPS Address Generating Mode ...................................................................9-3

Specifying the MPS Control ATM Address .....................................................................9-4

Setting the Control ATM Address Network Prefix .....................................................9-4

Setting the Control ATM Address User Part .............................................................9-5

Disabling and Reenabling Individual MPOA Servers ...... ....... ...... ...... ....... ...... ....... ...... ...9-6

Specifying the MPS Configuration Mode ........................................................................9-7

Specifying a LECS ATM Address ...................................................................................9-8

Defining the MPS Control ATM Address Selector Byte ................................................9-10

Defining MPS Timers ....................................................................................................9-11

Setting the Keepalive Time ....................................................................................9-11

Setting the Keepalive Lifetime ................................................................................9-12

Setting the Initial Retry Time ..................................................................................9-13

Setting the Maximum Retry Time ...........................................................................9-14

Setting the Give Up Time .......................................................................................9-15

Setting the Default Holding Time ...........................................................................9-16

Defining MPS Cache Values ........................................................................................9-17

Setting the Initial Cache Size .................................................................................9-17

Setting the Maximum Cache Size ..........................................................................9-18

Deleting an Individual MPS ..........................................................................................9-19

Deleting MPOA from the Interface ................................................................................9-20

Where to Go Next .........................................................................................................9-21

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Chapter 10 Customizing ATM Router Redundancy

Setting the ATM Router Redundancy Monitoring Timer ...............................................10-2

Where to Go Next .........................................................................................................10-3

Chapter 11 Customizing MPLS Configuration

Customizing LDP Parameters ......................................................................................11-2

Disabling and Reenabling LDP ....................................... ...... ...... ....... ...... ....... ...... .11- 2

Changing the Local IP Address ..............................................................................11-3

Specifying a Local TCP Port ..................................................................................11-4

Specifying a Remote IP Address ...........................................................................11-5

Specifying a Remote TCP Port ..............................................................................11-6

Specifying the Routes Configuration Mode ............................................................11-7

Specifying a Hold Time ..........................................................................................11-8

Specifying a Protocol for MPLS Route Configuration .............................................11-9

Enabling and Disabling Aggregation ....................................................................11-10

Disabling and Reenabling MLM Administrative Status ...............................................11-11

Customizing Default VC Parameters ..........................................................................11-12

Disabling and Reenabling Default VC Admin Status ............................................11-12

Specifying the Default VCL VPI Number ..............................................................11-13

Specifying the Default VCL VCI Number .............................................................11-14

Specifying the Default VC VPI Range ..................................................................11-15

Specifying the Default VC VCI Minimum Range ..................................................11-16

Specifying the Default VC VCI Maximum Range .................................................11-17

Modifying Default VC Traffic Parameters ..............................................................11-18

Setting the Default VC Transmit PCR ............................................................11-18

Setting the Default VC Transmit SCR ............................................................11-19

Setting the Default VC Transmit MBS ............................................................11-20

Setting the Default VC Receive PCR .............................................................11-22

Setting the Default VC Receive SCR .............................................................11-22

Setting the Default VC Receive MBS ............................................................11-24

Modifying the Default VC Maximum AAL CPCS SDU Size ..................................11-25

Setting the Transmit SDU Size ......................................................................11-25

Setting the Receive SDU Size .......................................................................11-26

Specifying the AAL Encapsulation Type ...............................................................11-27

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Specifying the Default VC Transmit QOS Class ...................................................11-28

Specifying the Default VC Receive QOS Class ...................................................11-28

Specifying the Default VC AAL Type ....................................................................11-28

Specifying the Default VC Congestion Indication .................................................11-28

Enabling and Disabling the Default VC Cell Loss Priority ....................................11-28

Enabling and Disabling Default VC Transmit Tagging ..........................................11-28

Enabling and Disabling Default VC Receive Tagging ...........................................11-28

Customizing LDP Static Route Parameters ................................................................11-29

Enabling and Disabling Static Routes ..................................................................11-29

Specifying a Destination Route Prefix ..................................................................11-30

Specifying a Route Mask .....................................................................................11-31

Where to Go Next .......................................................................................................11-33

Appendix A Site Manager Parameters

Accessing ATM Parameters ........................................................................................... A-2

Using the Window Path ........................................................................................... A-2

Select Connection Type Window ...................................................................... A-2

Edit ATM Connector Window ............................................................................ A-3

Edit MPLS Connector Window ......................................................................... A-4

Using the Menu Path ............................................................................................... A-4

Accessing Global ATM Signaling Attributes ...................................................... A-5

Accessing Global ATM Interface Attributes ....................................................... A-5

ATM Line Parameters .................................................................................................... A-6

ATM Interface Parameters ........................................................................................... A-12

ATM Service Record Parameters ................................................................................ A-15

ATM Virtual Channel Link Parameters ......................................................................... A-21

LAN Emulation Parameters ......................................................................................... A-27

LES Parameters .......................................................................................................... A-37

ATM Signaling Parameters .......................................................................................... A-39

ATM ILMI Signaling Parameters .................................................................................. A-55

Signaling and ILMI Control VC Parameters ................................................................. A-58

ATM Signaling AAL Parameters ................................................................................... A-63

MPOA Parameters ....................................................................................................... A-67

ATM Router Redundancy Parameter ........................................................................... A-75

OAM Parameters ......................................................................................................... A-76

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MPLS Parameters ....................................................................................................... A-79

LDP Parameters .................................................................................................... A-79

MLM Parameter ..................................................................................................... A-83

Static Route Parameters ....................................................................................... A-83

Default VC Parameters ......................................................................................... A-84

NHRP Parameters ....................................................................................................... A-94

ATMARP Parameters ................................................................................................. A-102

Adjacent Host Parameters ......................................................................................... A-104

Appendix B Monitoring ATM Using the BCC show Command

show atm interfaces ....................................................................................................... B-2

show atm line ................................................................................................................. B-3

show atm services ......................................................................................................... B-6

show atm signaling ........................................................................................................ B-6

show atm stats vcs ........................................................................................................ B-7

show atm vcs ................................................................................................................. B-8

show classical-ip configuration ...................................................................................... B-9

show classical-ip interface ............................................................................................. B-9

show classical-ip stats ................................................................................................. B-10

show classical-ip table ................................................................................................. B-10

show dsx3 circuits ....................................................................................................... B-11

show dsx3 current ....................................................................................................... B-12

show dsx3 history ........................................................................................................ B-15

show lane clients ......................................................................................................... B-19

show lane configuration ............................................................................................... B-20

show lane data-vcs ...................................................................................................... B-20

show lane le-arp .......................................................................................................... B-21

show lane le-rd-arp ...................................................................................................... B-22

show lane les ............................................................................................................... B-23

show lane macs ........................................................................................................... B-23

show lane servers ........................................................................................................ B-24

show lane stats ............................................................................................................ B-25

show sonet circuits ...................................................................................................... B-26

show sonet current ...................................................................................................... B-27

show sonet history ....................................................................................................... B-30

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Appendix C Configuring NHRP for ATM Services

NHRP Overview ............................................................................................................C-2

NHRP Message Exchange ..................................................................................... C-2

Configuring NHRP on an Unconfigured ATM Interface ..................................................C-3

Adding NHRP to an Existing ATM Interface ................................................................... C-6

Editing an NHRP Record ............................................................................................... C-8

Disabling an NHRP Record ...........................................................................................C-9

Deleting NHRP ..............................................................................................................C-9

Index

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Figures

Figure 1-1. ATM Cell ...................................................................................................1-2

Figure 1-2. ATM Cell Header ......................................................................................1-3

Figure 1-3. ATM Transmission Components ...............................................................1-5

Figure 1-4. B-ISDN ATM Protocol Reference Model ..................................................1-6

Figure 1-5. ATM Adaptation Layer 5 ...........................................................................1-9

Figure 1-6. Multiple PVCs per Service Record ........................................................1-17

Figure 1-7. One PVC per Service Record ................................................................1-19

Figure 1-8. Hybrid Access PVCs ..............................................................................1-20

Figure 1-9. Example of a Bridged Network ..............................................................1-21

Figure 1-10. ATM Address Components ....................................................................1-22

Figure 1-11. IP Local Area Network ...........................................................................1-29

Figure 1-12. IP Logical IP Subnet ..............................................................................1-30

Figure 1-13. LAN Emulation States ............................................................................1-36

Figure 1-14. MPOA with Cut-Through VC ..................................................................1-42

Figure 1-15. Router Redundancy ...............................................................................1-43

Figure 2-1. The MPLS System ...................................................................................2-3

Figure 2-2. Sample MPLS Network ............................................................................2-5

Figure 5-1. SVC/PVC Signaling Protocol Stack .........................................................5-2

Figure 5-2. SVC/PVC Signaling Protocol Stack .......................................................5-57

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Tables

Table 1-1. Maximum Bandwidth by Media Type ........................................................1-8

Table 1-2. Protocols Supported for Standard PVCs and SVCs .............................1-10

Table 1-3. Locating and Using Site Manager Protocol Menus ................................1-12

Table 1-4. Assigning Data Encapsulation to Individual PVCs .................................1-16

Table 3-1. Service Record Protocol Support ............................................................3-6

Table 3-2. Valid Data Encapsulation Types for PVCs and SVCs ..............................3-9

Table 4-1. Supported Framing Modes for ATM Interfaces .........................................4-9

Table 5-1. Signaling Timer Descriptions ..................................... ....... ...... ....... ....... 5 -15

Table 5-2. Valid PCR Ranges .................................................................................5-41

Table 5-3. Valid SCR Ranges .................................................................................5-45

Table 5-4. SSCOP/SAAL Timer Descriptions ........................................................5-61

Table 6-1. Valid PCR Ranges .................................................................................6-11

Table 6-2. Valid SCR Ranges .................................................................................6-13

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Preface

This guide describ es as ynchro nous transf er mode (ATM) and Mult ipro tocol Lab el Switching (MPLS) and what you do to star t and cus tomize t hese serv ices on a Bay

Networks You can use the Bay Command Console (BCC

ATM on a router. BCC supports some ATM features. However, some features are not supported and must be configured using Site Manager. In this guide, you will find instructions for using both the BCC and Site Manager.

To configure MPLS, you must use Site Manager.

router.

™

) or Site Manager to configure

Before You Begin

Before using this guide, you must complete the following procedures. For a new router:

• Install the router (see the installation guide that came with your router).

• Connect the router to the network and create a pilot configuration file (see Quick-Starting Routers).

Make sure that you are running the latest version of Bay Networks BayRS Site Manager software. For information about upgrading BayRS and Site Manager, see the upgrading guide for your version of BayRS.

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™

and

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Configuring ATM and MPLS Services

Text Conventions

This guide uses the following text conventions:

angle brackets (< >) Indicate that you choose the text to enter based on the

description inside the brackets. Do not type the brackets when entering the command. Example: If the command syntax is:

ping

<ip_address>

ping 192.32.10.12

, you enter:

bold text

Indicates text that you need to enter and command names and options. Example: Enter

show ip {alerts | routes

Example: Use the

dinfo

command.

}

braces ({}) Indicate required elements in syntax descriptions

where there is more than one option. You must choose only one of the options. Do not type the braces when entering the command. Example: If the command syntax is:

show ip {alerts | routes show ip alerts or show ip routes

, you must enter either:

}

brackets ([ ]) Indicate optional elements in syntax descriptions. Do

not type the brackets when entering the command. Example: If the command syntax is:

show ip interfaces [-alerts show ip interfaces

, you can enter either:

]

show ip interfaces -alerts

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Preface

ellipsis points (. . . ) Indicate that you repeat the last element of the

command as needed. Example: If the command syntax is:

ethernet/2/1 [< ethernet/2/1 and as many parameter-value pairs as

parameter> <value>

] . . ., you enter

needed.

italic text Indicates file and directory names, new terms, book

titles, and variables in command syntax descriptions. Where a variable is two or more words, the words are connected by an underscore. Example: If the command syntax is:

show at <

valid_route

valid_route>

is one variable and you substitute one value

for it.

screen text Indicates system output, for example, prompts and

system messages. Example:

Set Bay Networks Trap Monitor Filters

separator ( > ) Shows menu paths.

Example: Protocols > I P ide nti fies the IP option on the Protocols menu.

vertical line (

) Separates choices for command keywords and

arguments. Enter only one of the choices. Do not type the vertical line when entering the command. Example: If the command syntax is:

117374-C Rev 00

show ip {alerts | routes}, you enter either: show ip alerts or show ip routes, but not both.

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Configuring ATM and MPLS Services

Acronyms

AAL ATM adaptation layer ABR available bit rate AFI authority and format identifier AIS alarm indication signal ALC adaptation layer controller ARE ATM Routing Engine ARP Address Resolution Protocol ATM asynchronous transfer mode BFE Blacker front-end encryption B-ISDN Broadband Integrated Services Digital Network BUS broadcast and unknown server CLP cell loss p riority CPCS common part convergence sublayer

xxvi

CS convergence sublayer CSU channel service unit DCE data communication equipment DDN Defense Data Network DSU data service unit DTE data terminal equipment ELAN emulated local area network ER error recovery FIB forwarding information base HEC header error control IETF Internet Engineering Task Force ILI Intelligent Link Interface ILMI Interim L ocal Management Interface IP Internet Protocol

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Preface

IPX Internetwork Packet Exchange ITU-T International Telecommunication Union - Telecommunication

Standardization Sector LANE local area network emulation LDP label distribution protocol LE LAN emulation LEC LAN emulation client LECS LAN emulation configuration server LER label edge router LES LAN emulat ion server LIS logical IP subnet LLC Logical Link Control LUNI LAN emulation UNI MAC media access control MBS maximum burst size MCR minimum cell rate MCS multicast server MIB management inform ation base MPC Multi-Protocol over ATM client MPLS Multiprotocol Label Switching MPOA Multi-Protocol over ATM MPS MPOA server MTU maximum transmission unit NHRP Next Hop Resolution Prot ocol NML Native Mode LAN NMS network management station NNI network-to-network inte rface OAM Operations and Management OAM&P Operations, Administration, Maintenance and Provisioning

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Configuring ATM and MPLS Services

OC-3 Optical Carrier-level 3 OSI Open Systems Interconnection OSPF Open Shortest Path First PCR peak cell rate PD poll data PDN Public Data Network PDU protocol data unit PHY physical [layer] PMD physical medium dependent PT payload type PVC permanent virtual circuit RDI remote defect indication RIP Routing Information Protocol RS resynchronization SAAL signaling AAL

xxviii

SAP service access point SAR segmentation and reassembly SCR sustainable cell rate SD sequenced data SDU service data unit SMDS Swit ched Multimegabit Data Service SNAP Subnetwork Access Protocol SNMP Simple Network Management Protocol SONET/SDH Synchronous Optical Network/Synchronous Digital Hierarchy SPE synchronous payload envelope SRM System Resource Module SSCOP Service Specific Connection Oriented Protocol SSCS service specific converge nce sublayer STP shielded twisted pair

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SVC switched virtual circuit TOH transport overhead UNI user-to-network interface UTP unshielded twisted pair VBR variable bit rate VC virtual circuit VCC virtual channel connection VCI virtual channel identifier VCL virtual channel link VPC virtual path connection VPI virtual path identi fier WAN wide area network

Bay Networks Technical Publications

Preface

117374-C Rev 00

You can now print Bay Networks technical manuals and release notes free, directly from the Internet. Go to support.baynetwork s.com/libr ary/ tpubs/ . Fi nd the Bay Networks product for which you need documentation. Then locate the specific category and model or version for your hardware or software product. Using Adobe Acrobat Re ader, you can open the manuals and r eleas e note s, sea rch for the sections you need, and print them on most standard printers. You can download Acrobat Reader free from the Adobe Systems Web site, www.adobe.com.

You can purchase Bay Networks documentation sets, CDs, and selected technical publications through the Bay Networks Collateral Catalog. The catalog is located on the World Wide Web at support.baynetworks.com/catalog.html and is divided into sections arranged alphabetically:

• The “CD ROMs” section lists available CDs.

• The “Guides/Books” section lists books on technical topics.

• The “Technical Manuals” section lists available printed documentation sets.

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Configuring ATM and MPLS Services

Make a note of the part numbers and prices of the items that you want to order. Use the “Marketing Collateral Catalog description” link to place an order and to print the order form.

How to Get Help

For product assi stance, support contracts, information about educational services, and the telephone numbers of our gl obal supp ort offices, go to the following URL :

http://www.baynetworks.com/corpor ate/ conta cts/

In the United States and Canada, you can dial 800-2LANWAN for assistance.

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Chapter 1

Understanding ATM, MPO A,

ATM Router Redundancy, and OAM

This chapter describes the concepts underlying ATM and, where appropriate, the specific ways Bay Networks implements these concepts on its routers. It contains the following information:

Topic Page

ATM General Information 1-2 Classical IP over ATM Concepts 1-28 ATM LAN Emulation Concepts 1-33 Multi-Protocol ov er ATM Concepts 1-39 ATM Router Redundancy Concepts 1-43 PVC Operations and Management Concepts 1-44 For More Information 1-46 Where to Go Next 1-47

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Configuring ATM and MPLS Services

ATM General Information

Asynchronous transfer mode (ATM) is a connection-oriented, cell-based technology that relays traffic across a Broadband Integrated Services Digital Network (B-ISDN). ATM provides a cost-effective way of transmitting voice, video, and data across a network.

ATM Cells

An ATM cell is a fixed-length packet of 53 bytes. It consists of a 5-byte header containing address information and a fixed, 48-byte information field. Figure 1-1 shows a diagram of an ATM cell.

5-byte

header

Figure 1-1. ATM Cell

48-byte

information field

ATM0001A

This fixed-length cell size allows you to predict network delays, making ATM suitable for carrying real-time information (for example, voice and video) as well as data.

ATM allows the network to operate at a much higher rate than typical packet-switching protocols (for example, X.25), because it provides no error protection or flow control. Instead, ATM relies on the source and destination devices to perform er ror-recovery functions such as retra nsmissi on of lost pack et s.

1-2

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Understanding ATM, MPOA, ATM Router Redundancy, and OAM

Cell Header

After dividing the data into 48-byte segments for transmission, the end device -- that is, the ATM da ta ser vice un it/c hann el ser vice un it (DSU/CSU) or native ATM device -- attaches the required header information (Figure 1-2

5-byte

header

Bits

2345678

Generic flow control (GFC)

Virtual path identifier (VPI) Virtual channel identifier (VCI)

Virtual channel identifier (VCI)

Header error control (HEC)

48-byte

information field

Virtual path identifier (VPI)

Payload type (PT)

Figure 1-2. ATM Cell Header

The fields in each ATM cell header provide all the information necessary for networking. These fields include the following:

• Generic flow control (GFC): The first 4 bits of the cell header contain the GFC. The GFC controls traffic flow onto the ATM network by contr olli ng the user-to-network interface (U NI).

Cell loss

priority

3 4

Bytes

ATM0002A

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• V irt ual path id entifier (VPI): The next 8 bits of the cel l heade r (tha t is, the las t half of byte 1 and the first half of byte 2) contain the VPI. The VPI specifies a virtual path on the physical ATM link. See the next section, “Data Transmission,” for additional information about virtual paths.

1-3

Configuring ATM and MPLS Services

• Virtual channel identifier (VCI): The next 16 bits of the cell header (that is, the last half of b yte 2, b yte 3, a nd the first half of byte 4) contain the VCI. Th e VCI specifies a virtual channel within the virtual path on the physical ATM link. See the next section, “Data Transmission,” for additional information about virtual channels.

• Payload type (PT): The next 3 bits (that is, b it s 5 through 7 of byte 4) indicat e the type of information the cell is carrying (for example, user data or management information).

• Cell loss priority (CLP): The last bit of byte 4 indicates the priority of the cell and whether the network can discard the cell under heavy traffic conditions. Setting the bit to 1 indicates the network may discard the cell if necessary.

• Header error control (HEC): The last byte of the header field contains the HEC. Its primary function is to guard against misdelivery of cells due to header or single-bit errors. However, the HEC does not gauge the quality of the data in the information field.

Cell Information Field

Following the 5-byte cell header is a 48-byte information field containing user data. The ATM adapta ti on l ayer (AAL) organizes the data in thi s field. See “ATM

Layers” on page 1-6 for additional information about the AAL.

Data Transmission

Data transmission (also called cell switching) through the ATM network relies on the establishment of logical connections between ATM devices. ATM is a connection-oriented service. This means that an ATM device cannot transmit information until it establishes a connection with a receiving device. These connections consist of virtual channels, virtual paths, and transmission paths.

A virtual channel is a logical connection between two communicating ATM devices. Each virtual channel can carry a different protocol or traffic type. The virtual channel tra nsport s cel ls tha t ha v e a c ommon ide ntifier, the VCI, that is part of the cell header. You can establish virtual channels permanently or set them up dynamically, allowing the network to adjust itself to the traffic demand.

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Understanding ATM, MPOA, ATM Router Redundancy, and OAM

A virtual path is a set of virtual channels between a common source and destination. The virtual channels in a virt ual path are logically associated with a common identifi er, the virtual path identifier (VPI), that is part of the cell header. You can base cell switching on either the VPI alone, or on a combination of the VPI and VCI.

V irt ual paths en able you t o separa te networ k trans por t funct ions in to thos e relat ed to an individual logical connection (virtual channel) and those related to a group of logical connections (virtual path).

A transmission path is a physical connection that comprises several virtual paths, each virtual path containing several virtual channels. The transmission path can support multiple virtual paths across a single connection to the network.

Figure 1-3

shows the relationships betw een the vir tual channel, the virtual path,

and the transmission path.

Transmission Path

Figure 1-3. ATM Transmission Components

VP VP

VP = Virtual path VC = Virtual channel

VP VP

ATM0006A

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1-5

Configuring ATM and MPLS Services

Permanent and Switched Virtual Connections

Virtual channels and virtual paths allow you to establish virtual channel links (VCLs). You can create VCLs as ei ther permanent virtual circuits (PVCs) or switched virtual circuits (SVCs). After you establish a PVC, you can transfer information over it at any time. SVCs activate, through signaling and network switching, only when there is information ready for transmission.

ATM Layers

The B-ISDN protocol reference model, on which ATM is based, consists of four layers (Figure 1-4 and the layer directly below it.

). Each layer communicates only wit h the l ayer di rect ly abo v e i t

Higher protocol layer

Convergence sublayer (CS)

Segmentation and reassembly sublayer (SAR)

ATM layer

Transmission convergence sublayer

Physical medium dependent sublayer (PMD)

Figure 1-4. B-ISDN ATM Protocol Reference Model

ATM

adaptation

layer

(AAL)

Physical

layer

(PHY)

ATM0003A

1-6

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Understanding ATM, MPOA, ATM Router Redundancy, and OAM

The following layers relate directly to how Bay Networks routers support ATM:

• Physical layer

•ATM layer

• ATM ada ptation layer (AAL)

Physical Layer

In a Bay Networks Backbone Node (BN

) router, Intelligent Link Interface (ILI) pairs provide access and processing. An ILI pair consists of a link module and a processor module that work together to process and transmit information over a network. Bay Networks provides an ATM Routing Engine (ARE) link module in conjunction with an ARE processor.

In addition, Bay Networks provides a hub version of the ATM ARE ILI pair, the Model 5782 ATM router. This single hub module, incorporating the ILI functions of both the link module and processor module, resides in a System 5000BH chassis. See Using the Model 5782 ATM Virtual Network Router for more information.

The ILI pair and the Model 5782 ATM router are functionally identical, and you configure them in much the same way. Unless otherwise noted, the remainder of this guide treats the router ILI pair and the Model 5782 as if they were the same.

Depending on the ATM router type, you can connect directly to an ATM network over any of the following phys ical interfaces:

• Optical carrier level 3 (OC-3)

• Digital s ervice level 3 (DS-3)

• E-3 (the European equivalent of the North American DS-3)

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Configuring ATM and MPLS Services

Although Bay Networks uses raw bandwidth to describe line rates, inherent overhea d wit hin the me di a li mit s maxi mum band width for the line. Use Table 1-1 to determine the maximum bandwidth for the media you are using.

Table 1-1. Maximum Bandwidth by Media Type

Raw

Media

OC-3 SONET/SDH 155 149.76 353207 DS-3 (Cbit and M23

framing) E-3 (G.832 framing) 34.368 33.920 80000 E-3 (G.751 framing) 34.368 30.528 72000

Bandwidth (Mb/s)

44.736 40.704 96000

Maximum Bandwidth (Mb/s) Maximum Cells/s

ATM Layer

The ATM layer d efines how two nodes transmit in formation between them. It is concerned with the format and size of the cells and the contents of the headers. The addresses of the cells are meaningful only to the two adjacent local nodes (that is, usually not to the end nodes).

ATM Adaptation Layer

The ATM adaptation layer (AAL) converts upper-layer protocol data into formats that are compatible with the requirements of the ATM layer, enabling ATM to handle different t ypes of infor mation within the same format.

The AAL is divided into two sublayers: the convergence sublayer (CS) and the segmentation and reassembly (SAR) sublayer. These two sublayers convert variable-length messages into 48-byte segments, while ensuring the integrity of the data.

1-8

The CCITT (now ITU-T) has defined different types of AALs to handle different kinds of traffic. Bay Networks ATM routers support a CS function compatible with AAL 5, as defi ned in Section 1 of the CCITT (now ITU-T) B-ISDN Protocol Reference Model (PRM).

In AAL 5, only a trailer attaches to the data from the upper-layer protocols to create a CS PDU. AAL 5 divides the protocol data uni t (PDU) into a 48-octet SAR PDU; howe v er , it does not add an SAR header and trailer. This 48-octet SAR PDU becomes the payload of the ATM cell (Figure 1-5

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Understanding ATM, MPOA, ATM Router Redundancy, and OAM

Service class

AAL 5

convergence

sublayer

AAL layer

AAL 5

SAR

layer

ATM layer

Note: AAL 5 does not attach an SAR header or trailer to the PDU.

Figure 1-5. ATM Adaptation Layer 5

Service Records and Virtual Circuits

SAR PDU

ATM cell

Service data unit (SDU)

SDU

SAR PDU

ATM cell

Trailer

SAR PDU

ATM cell

ATM0005A

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ATM devices communicate using virtual circuits (VCs). These VCs transmit and receive ATM cells containing upper-layer protocols. Bay Networks ATM routers use service records to provide a way of creating logical interfaces (within the physical ATM interface) for these upper-layer protocols. In essence, these service records allow you to:

• Organize multiple VCs into logical groups.

• Create direct point-to-point connections.

• Assign, delete, and modify upper-layer protocols for just one PVC or for a

group of VCs at any given time.

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Configuring ATM and MPLS Services

Supported Protocols

Depending on the data encapsulation type and virtual connection type (PVC or SVC) you choose for the service record, the router supports various protocols.

Table 1-2

lists all supported protocols for standa rd PVCs and SVCs using

LLC/SNAP, NLPID, NULL, LANE 802.3, or LANE 802.5 data encapsulation.

Table 1-2. Protocols Supported for Standard PVCs and SVCs

PVC Using LLC/SNAP, NLPID, or NULL

Bridge IP Bridge Bridge

Spanning Tree RIP Spanning Tree Spanning Tree Native Mode LAN BGP Native Mode LAN

RIP EGP BGP BootP BGP OSPF OSPF BootP RIP/SAP BootP Router Discovery IGMP IGMP SR Spanning Tree

DVMRP DVMRP Translate/LB

NetBIOS NetBIOS DECnet IV DECnet IV DLSw VINES VINES APPN IPX IPX

RIP/SAP RIP/SAP OSI XNS Source Routing

SR Spanning Tree

Translate/LB XNS DLSw

RIP (XNS) AppleTalk

SVC Using LLC/SNAP or NULL (RFC 1577) SVC Using LANE 802.3 SVC Using LANE 802.5

OSPF

IPv6

RIP OSPF

RIP (XNS) AppleTalk LLC2

RIP

IPX

Source Routing

LLC2

1-10

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Understanding ATM, MPOA, ATM Router Redundancy, and OAM

Caution:

Ethernet and token ring emulated LANs can support different protocols. When adding a protocol to a LANE service record with an unspecified emulated LAN type, ensure that the protocols you add are supported by the emulated LAN (Ethernet or token ring) that you want to join.

Things to Remember

When enabling protocols on a service record, keep the following in mind:

• A PVC service record requires that you add at least one PVC for the service

record to operate.

• Each ATM service record globally controls:

-- All protocols for any standard PVCs and SVCs that it contains

-- All nonbridging protocols for any hybrid PVCs that it contains

• Selecting LANE to run on an SVC service record defines that service record

as belonging to an emulated LAN. Any protocols on that service record operate as if they were running over a traditional Ethernet or token ring LAN.

• When running IP over a NULL encapsulated PVC service record, you must

change the A ddress Resolution parameter to None. You must then add an IP adjacent host with the MAC address equal to the VPI/VCI of the PVC. See Configuring IP Services for information about the Address Resolution parameter.

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Configuring ATM and MPLS Services

Rules for Editing Protocols

Depending on the type of virtual circuit you are using, Site Manager requires you to add additional protocols, or delete and edit existing protocols, from specific protocol menus.

Use Table 1-3

Table 1-3. Locating and Using Site Manager Protocol Menus

Site Manager Menu Location PVCs and SVCs Hybrid PVCs Only

ATM Service Records List window ATM Virtual Channel Link window

* For nonbridging protocols

†

For bridging protocols

to locate the appropriate protocol menu for each access mode.

Remember, hybrid PVCs use their service record configurations for nonbridging protocols and their individual configurations for bridging protocols.

Data Encapsulation Methods

Bay Networks ATM routers support multiprotocol encapsulation (as defined in RFC 1483), enabling the ro uter to mul tiple x (combine) and demulti ple x (separa te) bridged or routed protocol data units (PDUs).

For transmission, the encapsulation process adds a header from 2 to 8 octets in length to the PDU to a llow decoding. The decoding process det ermine s the pro per service access point (SAP).

†

1-12

When receiving information, the encapsulation method evaluates the header to determine whether the PDU is a valid routed or bridged cell. If it is valid, the encapsulation met hod then s trips t he hea der fro m the ce ll and p asses th e cell t o the appropriate SAP for routing or bridging.

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You can choose from four data encapsulation types:

• LANE

• LLC/SNAP

• NULL

• NLPID How you assign a data encapsulation type and which type takes precedence

depends on the virtual circuit type and, for PVCs, the order in which you assign the encapsulation type.

Each ATM device must encapsulate PDUs before sending them to the SAR sublayer.

LANE Encapsulation

LANE provides Ethernet (IEEE 802.3) or token ring (IEEE 802.5) encapsulation of ATM PDUs for transmission over an emulated LAN. You can assign LANE encapsulation to SVCs only.

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LLC/SNAP Encapsulation

Logical Link Control/Subnetwork Access Protocol (LLC/SNAP; RFC 1483) allows multip lexi ng of multi ple protocol s ov er a si ngle ATM vir tual circui t. In thi s approach, an IEEE 802.2 Logical Link Control (LLC) header prefixes each PDU. You can assign LLC/SNAP encapsulation to:

• PVC service records

• SVC service records

• Individual PVCs

Assigning LLC/SNAP to an SVC service record automatically uses the

Note:

technology defined in RFC 1577, Classical IP and ARP over ATM. For information about RFC 1577, see “Classical IP over ATM Concepts

page 1-28

” on

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Configuring ATM and MPLS Services

NULL Encapsulation

RFC 1483 refers to NULL encapsulation as “VC-based multiplexing.” This method performs upper-layer protocol multiplexing implicitly using ATM virtual circuits. You can assign NULL encapsulation to:

• PVC service records

• SVC service records

• Individual PVCs that are also members of an LLC/SNAP service record

Assigning NULL to an SVC service record automatically uses the

Note:

technology defined in RFC 1577, Classical IP and ARP over ATM. For information about RFC 1577, see “Classical IP over ATM Concepts

page 1-28

NLPID Encapsulation

You can use Network Layer Protocol ID (NLPID; RFC 1490) in an ATM environment for frame relay/ATM internetworking. You can assign NLPID encapsulation to PVC service records.

” on

Selecting a Data Encapsulation Method

Generally speaking, th e desi gners of these data e ncapsul atio n methods envisioned that NULL encapsulation would dominate in environments where the dynamic creation of large numbers of ATM VCs is fast and economical. These conditions usually exist in private ATM networks.

LLC/SNAP encapsulation is an alternative for environments in which it is not practical to ha v e a se parat e VC for e ach car ried pro tocol ( for e xa mple , if the ATM network supports only PVCs, or if billing depends heavily on the number of simultaneous virtual circ uits).

The choice of multiplexing methods that two ATM stations use to exchange connectionless network traffic depends on the type of virtual circuit involved:

• For PVCs, you select the multiplexing method when you manually configure

the connection.

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• For SVCs, the stations themselves negotiate the multiplexing method by

sending B-ISDN signaling messages. These messages include “low-layer compatibility” information that allows negotiation of AAL5 and the carrie d (encapsulated) pr otocol.

Routed and bridged PDUs are always encapsulated within the payload

Note:

field of the AAL5 CPCS PDU, regardless of the selected multiplexing method.

Selecting LLC/SNAP Encapsulation

When the same virtual circuit carries several protocols, select LLC/SNAP encapsulation. LLC/SNAP encapsulation attaches an LLC/SNAP header before the PDU. This header includes information that the receiving ATM station needs to properly process the incoming PDU. For bridged PDUs, this header also includes the type of the bridged media.

Selecting NULL Encapsulation (VC-Based Multiplexing)

In NULL enca psulation, the carried netwo rk protocol is identified implicitly by the virtual circuit connecting the two ATM stations. Because each protocol must travel over a separate virtual circuit, there is no need to include explicit multiplexing information in the payload of the PDU. For this reason, the bandwidth requirements and processing overhead remain minimal.

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You can either manually configure the carried protocol or let the signaling procedures negotiate it dynamically during call establishment.

NULL encapsulated cells do not receive a header in a routed environment. In a bridged environment, the content of the PDU itself includes the necessary information for bridging the multiplexed protocols.

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Configuring ATM and MPLS Services

Encapsulation Rules for PVCs

How you assi gn data encaps ulati on to individual PVCs depends to a degre e on th e data encapsulation type you assigned to the service record that contains those PVCs. Table 1-4 and hybrid PVCs that reside on these service records.

Table 1-4. Assigning Data Encapsulation to Individual PVCs

provides suggestions for assigning data encapsulation to PVCs

Service Record Data Encapsulation Type

LLC/SNAP NULL or LLC/SNAP LLC/SNAP NULL NULL or LLC/SNAP LLC/SNAP NLPID NLPID NLPID

Individual PVC Data Encapsulation Type

Hybrid PVC Data Encapsulation Type

When assigning a data encapsulation type to a PVC or group of PVCs, keep the following in mind:

• When you add a PVC, it reads and uses the data encapsulation type specified

in its ATM service record.

• You can globally assign a data encapsulation type to all nonhybrid PVCs in a

particular service record, or you can assign a data encapsulation type to individual group PVCs.

• If you change the data encapsulation value for the service record, all new

PVCs that you add to that service record use the new value.

• You must assign a data encaps ulati on type to h ybrid- mode PVCs individually.

You cannot assign data enca psulatio n to a hybri d-mode PVC using the service record.

• When you use the copy function, the new PVC uses the data encapsulation

type of the existing PVC.

1-16

• When running IP over a NULL encapsulated PVC service record, you must

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PVC Access Methods

You can set up PVCs to access an ATM network in the following ways:

• Multiple PVCs per service record

• One PVC pe r service reco rd

• Hybrid access PVCs

Multiple PVCs

Upper-layer pro tocols treat each service record on an ATM network interface as a single access point . These protocols use a single networ k address to send al l traf f ic destined for the network to the ATM network interface. Figure 1-6 conceptual drawing of multiple PVCs accessing an ATM network through each service record.

ATM

physical

interface

Service

record Upper-layer protocol

Service

record

Understanding ATM, MPOA, ATM Router Redundancy, and OAM

shows a

Site A

PVC PVC PVC

PVC PVC

ATM

network

Site B

Site C

Site D

Site E

ATM0018B

Figure 1-6. Multiple PVCs per Service Record

Configuring multiple PVCs per service record uses network addressing most efficiently. Although you need to configure each PVC manually, you need only define and associate protocols with the ATM network service record. All the PVCs that you configure for a given ATM service record carry the protocols that you select and configure to run on that service record.

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Configuring ATM and MPLS Services

When you configure multipl e PVCs per service recor d, all PVCs use the

Note:

data encapsulation type that you set for the ATM service record. See “Data

Encapsulation Methods” on page 1-12 for more information.

A configuration usi ng mult iple PVCs per service record works best in either fully meshed environments or in nonmeshed environments where systems not directly connected to each other ha ve no need to communicate. You can conf igure mult iple PVCs per service record as long as you do not need to separate protocols by PVC (that is, all PVCs accept the same protocols).

There are, however, ways to configure upper-layer protocols, such as IP or Internetwork Packet Exchange (IPX), to al low systems in nonmeshed ne tw orks to fully communicate. See the documentation for these protocols for more information.

One PVC

A configuration using one PVC per service record works the same way as one using multiple PVCs per service record. When you define only one PVC per service record, upper-layer protocols treat the ATM network as a series of direct point-to-point connections, viewing each PVC as an individual network interface.

1-18

You can configur e each PVC wi th different protocols and parameter set tings . This allows you to connect to dif fer ent netw ork si tes usin g, for e xample , dif fe rent type s of data encapsulation (Figure 1-7

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ATM

physical

interface

Upper layer

protocol

Service record

PVC

Figure 1-7. One PVC per Service Record

Assigning one PVC per service record allows you to dedicate a PVC to a particular protocol, but at the expense of some configuration overhead, memory, and address space.

This type of configuration is best suited to small, nonmeshed configurations or to configurations in which protocols must reside on separate PVCs.

Note:

The maximum number of PVCs you can configure in this way varies, depending on the configuration of the router, the number of protocols running on the circuits, and the number of routing entries.

ATM

network

Site A

Site B

ATM0020A

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Hybrid Access PVCs

PVCs do not typically allow bridging in nonmeshed environments. If your network combines bridging and routing over the same interface, you need to use the service record portion of each PVC for routing, while at the same time allowing bridging to operate. To do this, you must define the PVC as a hybrid/ bridged VC.

Defining the PVC as a hybrid/bridged VC allows the bridge to view each PVC as a separate bridge interface while allowing the routing protocols to view all PVCs as part of the same interface (Figure 1-8

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Configuring ATM and MPLS Services

Bridge protocol sees two interfaces to the network

Routing protocol

I = Interface

Bridge

protocol

Routing protocol sees one interface to the network

Figure 1-8. Hybrid Access PVCs

Use hybrid PVCs when creating nonmeshed network configurations that use both bridging and routing over a single ATM interface. These PVCs work best for spanning tree bridging.

Note:

When you define a PVC as a hybrid/bridged VC, Site Manage r provides additional Bridge, Spanning Tree, Source Routing (SR), SR Spanning Tree, Translational/Learning bridge (Translate/LB), and Native Mode LAN (NML) protocol options. These protocols run on the PVC along with the protocols defined in the ATM service record.

ATM network interface

Hybrid PVC

Direction of data

Site A

ATM network

Site B

ATM0012B

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Using Hybrid PVCs for Transparent Bridging

In Figure 1-9

, traff ic is bridged between site A and site B. The bridge (r out er 1) i s running on the ATM network interface, and its PVCs are not defined as hybrid/bridged VCs.

Site A Site B

Bridge port sees one path to Sites A and B

Router 1

ATM network

Figure 1-9. Example of a Bridged Network

Router 2

Router 3

ATM0013A

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In this exampl e, when the bridge receives da ta from site A and does not recognize the destination address, it tries to direct traffic through another bridge port. However, because the PVCs are not defined as hybrid/bridged VCs, the ATM bridge port views the paths to site A and site B as the same.

A bridge does not send the same data over the bridge port fr om which it just received the data, so the bridge cannot direct the data to site B. To resolve this problem, you need to designate the PVCs on router 1 as hybrid/bridged VCs.

If you define the PVCs as hybrid VCs, each PVC acts as a separate bridge port. This enables the bridge running on the ATM in terface to view the traffic from site A as arriving on a different port from that of site B. When the bridge sends data, it now has access to all its ports, including the port that accesses site B. Therefore, data from site A can reach site B.

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Configuring ATM and MPLS Services

SVC Access Methods

SVCs use signaling messages to dynamically establish, maintain, and clear a switched virtual connec tion at the UNI. These message s (as defi ned by the Q.2931 standard for signaling protocols) allow the router to assess the availability of an ATM end point (device), establish a connection with that device, mainta in that connection for the duration of data transfer, and then clear the connection when the transfer is complete.

Assigning ATM Addresses

An ATM address is composed of a network prefix and a user part. Bay Networks routers use the autogeneration feat ure to create the user part of the ATM address by combining the MAC address of the ATM interface with a unique selector byte to create unique addresses (Figure 1-10 manually.

390000000000000000000000000000A20CA98F00

). You can also enter ATM addr esses

ATM address

1-22

Network prefix

39000000000000000000000000

0000A20CA98F00

MAC address

0000A20CA98F 00

Figure 1-10. ATM Address Components

User part

Selector

byte

ATM0037A

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Entering an ATM Address Network Prefix

The ATM address network prefix specifies the ATM domain of which the service record is a part. This 13-byte portion of the ATM address can range from XX000000000000000000000000 to XXFFFFFFFFFFFFFFFFFFFFFFFF.

The XX byte must contain a value of 39, 45, or 47. These values define the authority and format identifier (AFI). The AFI byte identifies the group responsible for allocating the prefix and the format the p refix uses. For more information about the AFI byte, refer to the ATM Forum UNI specification.

Entering an ATM address ne twork pr ef ix is opt ional. If you do not e nter a netw ork prefix in the spe cif i ed r ange, t he ser vice r ec ord acc epts t he first prefix v alue t hat it receives from the switch.

Entering an ATM Address User Part

The ATM address user part (su ff ix) consi sts of a 6-byt e end-statio n identif ier and a 1-byte selector field. This 7-byte portion of the ATM address can range from 00000000000000 to FEFFFFFFFFFFFF.

You can either allow the router to generate this value automatically, or you can enter the value manually.

ATM Traffic Parameters

The ATM User-Network Interface Specification defines the following traffic parameters:

• Peak cell rate (PCR) -- The upper traffic rate limit for a n individual VC

• Sustainable cell rate (SCR) -- The upper bound on the conforming average

rate of an individual PVC or control VC

• Maximum burst s ize (MBS) -- Th e maximum length of a cell stream allowed

on a particular VC

These parameters help to prioritize and cont rol the traffic on each VC. How you configure your ATM traffic parameters depends on the characteristics of the individual c onnection s that you w ant to set up (for e xample, t he desired maximum cell rate, average cell rate, and burst size).

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Configuring ATM and MPLS Services

You can change ATM traffic parameters several times before deciding on a particular set. The following sections describe the traffic parameters and provide some basic guidelin es for customizing them on an ATM PVC or ATM control VC (that is, the signaling VC or ILMI VC).

You do not need to manually configure traffic parameters for SVCs (as

Note:

you must for PVCs and control VCs), because SVCs dynamically negotiate these parameters before sending data.

Using the PCR

The PCR specifies the upper traffic limit, in cells/second, that the ATM connection can support.

How you set the PCR de pends on:

• The optical transmission rate of your ATM device

• The amount of traffic you expect on a particular VC

• The rate you want for each VC When setting the PCR, keep the following considerations in mind:

1-24

• Each VC can have its own PCR.

• The PCR cannot exceed the maximum rate for the physical media. For

example, you cannot exceed 149.76 Mb/s for an OC-3c line.

• The PCR specifies the desired rate for the attached physical media (that is,

OC-3c, DS-3, or E-3). It does not specify the rate for the ATM network as a whole. For example, you can specify a full 149.76 Mb/s for each PVC or control VC on an OC-3c connection. However, if the VC ultimately connects to a lower-speed link (for example, T1 or E1), your PCR is limited to the maximum rate for that media.

• ATM VCs may fail to operate with PCR values lower than 128 cells/s.

• The E-3 framing mode setting affects the maximum PCR setting.

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Using the SCR

The SCR is the upper bound on the conf orming average rate of an indivi dual PVC or control VC. The average rate is the number of cells transmitted over the link divided by the duration of the connection. The duration of the connection is the total amount of time it takes from connection setup to connection release.

The SCR allows you to define future cell flow on a PVC or control VC in greater detail than by using only the PCR. The SCR controls the rate over time -- not at a specific instant of time -- and can help you use your ne twork resources more efficiently. In othe r words, the SCR allows sufficient bandwidth for operation, but does not allow a bandwidth as high as the PCR.

The SCR value maps directly to an MCR (minimum cell rate) value. In other words, when you conf igu re the SCR on a device, you actually configure th e uppe r bound of an a vera ge rate. Like t he SCR, the MCR def ines the minimum am ount of guaranteed bandwidth allowed for PVCs and control VCs on the ATM line. The MCR (that is, SCR) not only controls the rate over time, it guarantees this rate.

When setting the SCR, keep the following considerations in mind:

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• The SCR maps directly to the MCR.

• The MCR provides guaranteed bandwidth for PVCs and control VCs while

allowing sufficient ban dwidth for S VCs to opera te.

• To be useful, the SCR must not exceed the PCR.

• If you know the user average rate, set the SCR approximately 10 percent

higher than this value.

• ATM VCs may fail to operate with SCR values lower than 128 cells/s.

• Entering 0 for the SCR turns off this function and specifies that the ATM

router uses “best effort” for SCR.

• The E-3 framing mode setting affects the maximum SCR setting.

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Configuring ATM and MPLS Services

Using the MBS

The MBS specifies the maximum number of sequential cells allowed on a VC before that VC must relinquish bandwidth to other VCs waiting to transmit. This burst occurs at or close to the peak cell rate.

When setting the MBS, we suggest that you select a value larger than the largest packet your PVC or control VC can transmit (that is, the size of the maximum AAL CPCS transmit SDU). For example, if your VC accepts packets that are less than 4608 bytes long (PVC default), set your MBS value between 45 and 50 cells.

As a guideline, use this formula to determine your MBS value:

Maximum packet size (in bytes)

48 bytes/cell

For example:

4608 bytes (default)

48 bytes/cell

= MBS value (in cells)

= 96 cells

ATM0016A

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ARP and Inverse ARP Support

ATM supports the Address Resolution Protocol (ARP), enabling the router to dynamically resolve IP network layer protocol-to-VPI/VCI address mappings. ATM learns the address of the virt ual circuit by d etecting the virtual cir cuit that delivered the ARP response.

ATM also supports Inverse ARP. However, you can use Inverse ARP only if both the local and remote routers support it.

Bay Networks uses both pro prietar y and sta ndard ARP and Inverse ARP for PVCs that run IP. The method that the PVC uses depends on how you configure address resolution for the IP interface. See Configuring IP Services for additional information about configuring address resolution.

Bay Networks use s s ta ndar d ARP and Inverse ARP for SVCs r unni ng classical IP (RFC 1577) and SVCs running LAN emulation.

ATM Error Checking

ATM verifies that the VPI/VCI is valid with respect to the PVCs configured for the ATM circuit. It also verifies the header format. ATM verifies valid SVC connection through signaling messages.

Simulated Multicast Packet Support

Simulated multicasting is generally used in certain address resolution techniques and for applications that require the d elivery of identical information to multiple recipients. Bay Netwo rks ATM router s simulate mult icasti ng by se nding a cop y of the multicast or broadcast packet to every available virtual circuit on a particular logical interface.

Converting Mb/s to Cells/s

Several ATM traffic parameters require you to enter values in cells per second (cells/s). To convert to cells/s, divide the number of bits/s by 424 (the number of bits per ATM cell).

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Configuring ATM and MPLS Services

Number of bits/second

Number of bits/ATM cell

For example:

100,000,000 bits/s

424 bits/cell

Classical IP over ATM Concepts

RFC 1577, Classical IP and ARP over ATM, describes an administrative entity within an ATM network called a logical IP subnet (LIS). Each ATM LIS consists of multiple network de vice s -- hosts and router s -- connected to the ATM network and configured with interfaces to the same IP subnet.

Each LIS operates and communicates independently in an ATM network. A host connected to an ATM network communicates directly with other hosts in its own LIS. To communicate with hosts in another LIS, the host must use an IP router. This router c an connect to multiple LISs.

= Number of cells/second

= 235,849 cells/s

ATM0021A

1-28

An ATM LIS must meet the fo llowing requirements:

• All memb ers of the LIS (hosts and routers) must have the same IP network/

subnet address and mask.

• All members must be directly connected to the ATM network using SVCs.

• All members must access hosts outside the LIS through a router.

• All members must be able to communic ate by means of ATM with e very ot her

member of the LIS (that is, the virtual connection topology must be fully meshed).

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An ATM LIS can replace an IP LAN. In Figure 1-11, for example, three IP host systems and an IP router have interfaces to an Ethernet LAN. To communicate with each other on the LAN, the devices use the MAC addresses that they obtain using ARP or static routes. For communication beyond the LAN, the devices use IP addresses.

140.250.200.1 00 00A2 00 00 01

Host

140.250.200.4

00 00A2 00 10 40

ATM0035A

140.250.200.0

Host

140.250.200.2

00 00A2 00 10 20

Host

140.250.200.3

00 00A2 00 10 30

Router

Figure 1-11. IP Local Area Network

In Figure 1-12, an ATM network replaces the LAN interfaces, creating a LIS. For communication within the LIS, the devices use ATM addresses obtained using ATMARP; for communication beyond the LIS, the devices use IP addresses.

For example, to send a message to host B, host A uses host B’s ATM address. To send a message to a h ost beyond the LIS, host A uses an IP address to identify the remote host and sen ds the me ssage to t he local router ( route r A), using the rout er’s ATM address. The router then forwards the message.

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Configuring ATM and MPLS Services

ATMARP client

Router A

ATM network

ATMARP server

Host

Key

SVC supporting ATM LIS

Host

Figure 1-12. IP Logical IP Subnet

Router B

ATM0037A

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ATM Address Resolution

An address resolution protocol defines a mechanism that enables an IP router to use the IP address of a ne tw ork device to learn the physical addres s of th at device. An Ethernet LAN uses ARP as its address resolution scheme. A LIS uses an address resolution scheme called ATMARP as defined by RFC 1577.

On a LAN, defined as a broadcast medium, a router obtains the physical address of a network device by broadcasting an ARP request. In a LIS, which uses a nonbroadcast ATM medium, a router sends an ATMARP request to an ATMARP server.

Each IP interface on the LIS opens a V C to the ATMARP server and registers its IP address and ATM address (Figure 1-12 the server builds and maintains a table that maps LIS IP addresses to ATM addresses.

A router that needs the ATM address of a host on the LIS sends an ATMARP request to the server. When the server returns a response containing the address, the router extracts the ATM address of the host from the response and opens an SVC directly to the host using ATM UNI signaling.

on page 1-30). Using this information,

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If the server does not have an entry for the re quested IP address, it returns a negative acknowledgment, signifying that the destination is unreachable.

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Configuring ATM and MPLS Services

Configuring an ATM Service Record for ATMARP

When configuring a service record to act as an ATMARP client or server:

• Define a classical IP service record.

-- Specify SVC as the v irtua l circui t type for t he serv ice re cord. Al l netw or k devices on a LIS must connect ove r SVCs.

-- Specify LLC/SNAP or NULL as the encapsulation type for the service record. RFC 1577 defines LLC/SNAP as the encapsulation type for ATMARP.

For more information about how to create an SVC service record to run classical IP, see Chapter 3, “Starting ATM, ATM MPOA Server, ATM Router Redundancy, and MPLS.”

• Add IP and IP routing protocols to the circuit.

• Configure ATMARP Mode as either a client or a server. For a description of the ATM-specific IP parameters necessary for classical IP

ATMARP operation over ATM, see “ATMARP Parameters” on page A-102.

For full compatibility with RFC 1577, you may have to specify a maximum transmission unit (MTU) size of 9188 bytes. See “Defining the Interface MTU” on page 4-3 (for the BCC) or the Site Manager Interface MTU parameter description on page A-6 for additional information about setting the MTU size.

1-32

When configuring th e router as a client , you must def ine the serv er switch add ress. The client sends ATMARP requests to the server switch address.

Note:

If you remove and replace a link module that is configured as an ATMARP client, the client loses connectivity until the ATMARP server registration refresh interval for that client expires (900-second default). This loss of connectivity occurs only when the client is configured to autogenerate the ATM address user part (see “Disabling and Reenabling User Part Autogeneration” on page 7-4 for additional information about autogenerating ATM addresses).

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Configuring an ATM Address for an Adjacent Host

An adjacent host is a network device on the local LIS. You must configure an ATM address for all hosts on the LIS that do not use ATMARP.

For a description of the IP parameters required for creating adjacent hosts in a classical IP over ATM environment, see “Adjacent Host Parameters” on page A-104.

For more information about adding, editing, and deleting adjacent hosts, see Configuring IP Services.

ATM LAN Emulation Concepts

LAN emulation allows virtual communication of traditional LAN devices and applications over an ATM network. An ATM network can run one or more emulated LANs. However, each emulated LAN is independent of the others and devices cannot communicate directly across emulated LAN boundaries.

Note:

Communication between emulated LANs is possible through routers and bridges only (possi bly implemented on the same end station).

This section provides general information about LAN emulation as described by the ATM Forum. For more information about LAN emulation, refer to the ATM Forum document LAN Emulation Over ATM (Version 1.0).

For instructions on how to customize LAN emulation on your ATM router, see Chapter 8, “Customizing LAN Emulation Service Records and Clients.”

LAN Emulation Connectivity

An emulated LAN can provide Ethernet (IEEE 802.3) or tok e n rin g (IEEE 802.5) connectivity. With an emulated Ethernet or token ring network over ATM, software applications can interact as if they were connected to a traditional LAN.

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Configuring ATM and MPLS Services

LAN Emulation Components

Each ATM domain contains a LAN emulation configuration server (LECS). Each emulated LAN comprises a group of LAN emulation clients (LECs), a LAN emulation server (LES), and a broadcast and unknown server (BUS). These servers provide specific LAN emulation services.

LAN Emulation Configuration Server

The LAN emulation configuration server (LECS) assigns individual LE clients to different emulated LANs. The LECS does this by giving the client the ATM address of the LAN emulation server (LES). This method allows you to assign a client to an emulated LAN based on the client’s physical location (ATM address) or the identity of a LAN destination it re presents.

LAN Emulation Clients

The LAN emulation client (LE client or LEC) is the interface, or virtual portion of an interface, through which an end station forwards data, resolves addresses, and provides other control functions. The LE client provides the MAC-level emulated Ethernet or tok en rin g servic e int erfac e to the upper -lay er prot ocol. It also con trols the LAN emulation UNI (LUNI) interface when communicating with other devices on the emulated LAN.

1-34

The LE client uses the configuration protocol to obtain information from the LECS. This protocol allows the LE client to locate the LES and set up a bidirectional, control direct virtual channel connection. The LE client automatically obtains all of the necessary configurat ion data (including the LES address) from the LECS.

LAN Emulation Server

The LES controls and coordinates LE client access to the emulated LAN. When an LE client joins an emulat ed LAN, it registers its ATM address with the LES. When the LES obtains the ATM address of the LE client, it also obtains the client’s physical location (from the MAC address or route descriptor).

LE clients query the LES to obtain the ATM address associated with a specific MAC address or route descriptor. After an LE client receives the ATM address of the LE client it wants to reach, the individual clients communicate directly.

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Broadcast and Unknown Server

T o emulate a tradi tional LAN, the emul ated LAN must provi de the connect ionless data deli very of a shared network to its LE cl ie nts and be able to handle broadcast and multicast data. The broadcast and unknown server (BUS) fulfills this requirement by distributing all broadcast, multicast, and unknown traffic to and from all LE clients on an emulated LAN.

For example, when an LE client sets up its initial configuration, it obtains the MAC address of the BUS from the LES. Using this MAC address, the LE client sets up a multic ast se nd vir tual channe l conne ction (VCC) t o the B US. In tu rn, the BUS registers t he LE client as part of its emulated L AN.

To broadcast data, an LE client uses the multicast send VCC to transmit information to the BUS. The BUS then retransmits the data, through multiple point-to-point connections or one point-to-multipoint connection, to each LE client on the emulated LAN.

Redundant LES/BUS

Understanding ATM, MPOA, ATM Router Redundancy, and OAM

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Bay Networks ATM routers support LAN emulation server (LES) and broadcast and unknown server (BUS) redundancy. This redundancy reduces the risk of network failure by overcoming a single point of failure in accessing the LES.

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Configuring ATM and MPLS Services

LAN Emulation States

As defined in the ATM Forum LAN Emulation Over A T M specif ica tion, L E clients enter va ri ous st at es of communication while attempting to jo in an emulated LAN. These states (referred to as “phases” by the ATM Forum) indicate the progress of an LE client as it connects with an emulated LAN (Figure 1-13

Initial state (1)

LECS connect state (2)

After experiencing any failure, or terminating its connection to the emulated LAN, the LE client returns to the initial state.

Configure state (3)

Join state (4)

Initial registration state (5)

BUS connect state (6)

Operational state (7)

Figure 1-13. LAN Emulation States

Note:

The numbers that follow each state appear in the ATM LEC status record (wfAtmLecStatusEntry).

If the LE client loses the BUS connection, it can attempt to reconnect.

ATM0034A

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The following sections briefly describe each LAN emulation state. Refer to the ATM Forum LAN Emulation Over ATM specification for more information about LAN emulation states.

Initial State

An LE client always starts in the initial state before attempting to connect to the LECS.

LECS Connect State

An LE client enters the LECS connect state when it attempts to connect to the LECS.

Configure State

An LE client enters the configure state when it attempts to retrieve the necessary information (that is, the ATM address of the LES, LAN type, LAN name, Maximum MTU, and various timeout values) required to join an emulated LAN.

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Join State

An LE client enters the join state when it attempts to join an emulated LAN. Joining an emulated LAN requires that the LE client:

• Set up a control VCC to communicate with the LES.

• Send a join request (c ontaining the client MAC address) to the LES.

• Accept a control distributed VCC to receive control data from the LES.

• Receive a valid join response from the LES containing a LAN emulation

client ID (LECID).

Only one ATM LE client per Bay Networks ATM router can join an

Note:

emulated LAN at any point in time. However, you can always move a LAN emulation client t o t he app rop ri at e e mu la ted LAN us in g ne twork management software.

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Configuring ATM and MPLS Services

Initial Registration Sta te

An LE client enters the initial registration state when it attempts to register multiple MAC addresses with the LES.

The router LE client provides the MAC address only for its own ATM

Note:

interface. Because it does not register multiple MAC addresses, the router never enters this state. The router LE client acts as a proxy for bridge MAC addresses not lear ned on this circuit.

BUS Connect State

An LE client enters the B US connec t stat e when i t att empts t o set u p a VCC to th e BUS.

Operational State

An LE client enters the operational state after successfully completing the requirements to join an emulated L AN.

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Multi-Protocol over ATM Concepts

As defined by the ATM Forum, Multi-Protocol over ATM (MPOA) maps routed and bridged traffic flows to ATM SVCs, thus mitigating the performance limitations imposed by hop-by-hop routing of individual packets. This technique of mapping identifiable traffic flows to virtual channels creates network “shortcuts” between source and destination, and is generally referred to as cut-through or zero-hop routing.

Cut-through routing i s based o n the f act t hat, in most cases , data t ransfe r occur s at a steady rate of flow. For example, data or file transfer from one legacy Ethernet LAN to a remote counterpart usually involves multiple frames. A file transfer of approximately 45 KB requires about 30 Ether net frames, all address ed to the same destination.

In an MPOA environment, it is possible to identify the recipient from addressing data contained within the first frame and to establish an SVC to the recipient. Then all 30 or so frames can be broken down into approximately 900 ATM cells and transmitted to the recipient via the virtua l channel provided by the SV C.

Network performa nce i mp roves as the cells follow a predetermined direct path, in contrast to the hop-by-hop routing of the Ethernet frames. Network performance improves markedly in the case of steady-stream deterministic data flows, such as video.

MPOA Logical Components

MPOA operati ons are based on l ogical compone nts, which can be im plemented in various configurations of hardware and software. MPOA logical components include the following:

•MPOA client

The MPOA client (MPC) resides in an ATM edge device adjacent to the router. BayRS does not provide MPC functionality. The primary function of the MPC is to act, in ATM terminology, as an ingress or egress point for traffic using network cut-throughs.

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Configuring ATM and MPLS Services

The MPC moni tors traffic flows between a local source an d remote destinations. Wh en traffic volume between a s ource a nd a d estin ation e x cee ds a preconfigured threshold level (for example x packets to the same network layer address in y seconds), the MPC attempts to set up an SVC between the source and destination workstations.

In attempting to set up an SVC, the MPC first looks in a local cache of network layer-to-ATM address mappings. If the MPC finds the destination address in its local cac he, it immediately be gins to est ablish the SVC. If it f ails to locate the destination address in the local cache, it generates an MPOA address resolution request to an adjacent MPOA server.

• MPOA router

The MPOA router is a collection of logical functions that map network layer addresses to ATM addresses. The MPOA router maintains tables of adjacent network layer (IP), MAC layer, and ATM addresses, in addition to standard routing tables derived from a routing protocol (generally OSPF or RIP). MPOA routers communicate over NHRP to map network layer addresses to ATM addresses. BayRS provides MPOA router functionality to map IP addresses to their ATM counterparts.

• MPOA server

The MPOA server (MPS) is a logical function that mediates between local MPCs and the MPOA router. It receives MPOA address resolution requests from MPCs and passes them to the MPOA routing function. The MPOA router, using NHRP, resolves the address and passes the requested ATM address back to the MPS. The MPS, in turn, forwards the resolved address to the requesting MPC. BayR S provides MPOA server func tionality.

MPOA Basic Elements

MPOA services are dependent on three basic elements:

• LANE

LANE (LAN emulation) provides transparent support for legacy LANs in an ATM topology. LANE enables intrasubnet communication, and MPOA provides intersub net communication.

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• Next Hop Resolution Protocol (NHRP)

NHRP is a sophisticated address resolution protocol that maps network layer addresses (for example, IP addresses) to NBMA addresses (in the case of BayRS, ATM addresses). For instructions on conf iguring an NHRP serv er , see Appendix C, “Configuring NHRP for ATM Services.”

• Virtual router

A virtual router is a set of network devices and associated software that collectively provides the functionality of multiprotocol routed networks.

Establishing a Network Cut-Through

MPOA componen ts and elements fu nction together to establish an SVC bet ween a source host and a destination host (Figure 1-14

A local MPC monitors traf f ic f lo w and mainta ins a count of pack ets addre ssed over a specific interval to remote hosts. When the count exceeds a threshold value, the MPC attempts to establish an SVC to the host.

To establish the virtual connection, the MPC needs the ATM address of the host.

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The MPS first checks a local address re solution cache to map th e known network layer address with an ATM equivalent.

If the cache search fails, the MPC issues an MPOA resolution request to the local MPS function resident on the adjacent router.

The local MPS hands the resolution request to the MPOA router component.

The MPOA rou ter gener ates an NHRP address resolut ion reque st for t he ATM address of the destination host. Standard routing protocols move the NHRP request through the ne twork toward the destination host. Eventually, the NHRP request reaches the egress router, that is, th e router that serves the host.

The egress router forwards the request to the remote MPS.

The remote MPS provides the ATM address of the destination host to the remote MPOA router.

If the destination host is connected to a legacy LAN, the MPS provides the ATM address of the router that connects to the legacy LAN. If the destinat ion host is ATM-attached, the MPS provides the ATM address of the destination host.

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Configuring ATM and MPLS Services

The remote MPOA router generates an NHRP address resolution reply containing the ATM address provided b y th e MPS. Standar d routing pr otocols move the NHRP reply through the network to the local MPOA router.

After caching the addr ess resolution information, the MPOA router sends the resolved addr es s t o th e M PS, whi ch, i n t urn, sends the resolved address to the MPC that initiated the resolution process.

10.

The local MPC caches the ad dress reso lution inf ormati on and no w esta blishes an SVC, either directly t o t he de st ination host (if that host is an ATM device), or to the egress router that serves the dest ination host.

ATM MPC

10BASE-T

ATM network

ATM MPS

ELAN 1

ELAN 2

10BASE-T

ATM MPC

Figure 1-14. MPOA with Cut-Through VC

Note:

Creating a separate NHRP control VC is optional. If you configure NHRP on each LEC, the control information passes over the emulated LAN.

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ELAN 3

ELAN 4

ATM MPS

Key

Cut-through VC Logical connection

NHRP control VC

ATM0055A

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Understanding ATM, MPOA, ATM Router Redundancy, and OAM

ATM Router Redundancy Concepts

Bay Networ ks ATM routers support warm sta ndby router redundancy. This redundancy protects a network from the irrecoverable failure of an entire ATM router. You configure routers to be members of a router redundancy group.

Token ring

100BASE-T

10BASE-T

Token ring

Figure 1-15

Centillion 100 switch

illustrates rout er redundancy in a Bay Networks ATM environment.

ATM network

ATM router 1

ELAN 1

ELAN 2

ELAN 3

ELAN 4

Key

ATM router 2

Physical connection Logical connection

ATM00002

Figure 1-15. Router Redundancy

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Configuring ATM and MPLS Services

Router redundancy requires at least two routers to be members of a router redundancy group. One router acts as the primary router and provides normal routing/bridging services. The other router acts as the secondary, backup router and takes over if the primary router fails.

All members of an ATM router redundancy group must have the following characteristics:

• Be the same ATM router type, for example, BCN

• Have the same hardware configuration, including CPU and interface module

types, and slot and port locations of the backed-up interfaces.

• Have the same sof tw a re configuration. That is, you must be running the same

router software ve rs ion and have the same loadable modul es configured.

• Contain both a primary configuration file and a secondary configuration file.

• Have at least one legacy LAN connection between the routers in the

redundancy group.

Note:

Bay Networks recommends at least two legacy LAN connections between routers in the redundancy group.

, BLN®, or System 5000™.

PVC Operations and Management Concepts

In most ATM networks, if a PVC fails, the remote device does not receive notification of the failure at the ATM layer. Instead, the device receives this information from a non-ATM source such as a routing protocol that operates above the ATM layer. The PVC Operations and Management (OAM) feature provides a mechanism by which ATM devices can receive prompt failure information.

PVC OAM has two methods of detecting PVC failure: loopback and alarms. You can use either of these methods separately or both methods together. When using OAM loopback cells, the time can decrease to only a few seconds; when using OAM alarms, the detection is almost instantaneous.

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OAM Loopback

The OAM loopb ack meth od u ses lo opback c ells to det ect a lost connec tion. When OAM loopba ck is enabled, the PVC sends loopback cells at a designated interval. If a remote device does not return loopback responses, and the PVC loses a specified number of cells, the service record alerts the upper-layer protocol that the link is down . The PVC continues to se nd O AM loopbac k cells ov er the se rvice record. When it receives a specified number of OAM loopback responses, it declares the link operational and begins sending traffic again.

Note:

PVCs on an interface. Link status is based on the OAM loopback status of all PVCs on the in terface.

OAM Alarms

If the ATM router connects to an ATM switch that uses OAM alarms, you can enable alarm detection on the ATM router. With OAM alarms enabled, when the router recei ve s an alar m indicat ion signa l (AIS) a larm from the switch, i t alert s the upper-layer protocol that the ATM link is down; it does not wait for an OAM loopback response fr om the remote device.

Understanding ATM, MPOA, ATM Router Redundancy, and OAM

For OAM loopback to function properly, you must configure it on all

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After receiving an AIS alarm, the router sends a remote defect indication (RDI) response to the switch to indicate that it received the alarm. The switch continues to send AIS alarms u ntil the link is operat ional ag ain. If the rout er does not rece i ve an AIS alarm for 3 seconds, it declares the link operational and begins sending traffic again.

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Configuring ATM and MPLS Services

For More Information

For more information about ATM, refer to the following documents: ATM Forum. ATM User-Network Interface Specification. Version 3.0. September

1993. ATM Forum. LAN Emulation Over ATM. Version 1.0. January 1995. Bellcore Document SR-NWT-001763, Issue 1. Prelimi nar y Report on Broadband

ISDN Transfer Protocols. December 1990. ———, FA-NWT-001109. Broadband ISDN Transport Network Elements

Framework Generic Criteria. December 1990. ———, FA-NWT-001110. Broadband ISDN Switching System Framework

Generic Criteria. December 1990. De Prycker , M. Asynchr onou s T r ansfer Mode: Soluti on for Br oad band ISDN. Ellis

Horwood Limited, 1991. Grossman, D., E. Hoffman, F. Liaw, A. Malis, A. Mankin, and M. Perez. ATM

Signaling Support for IP over ATM. RFC 1755. Network Working Group. February 1995.

1-46

Handel, R., and M. Huber. Integrated Broadband Networks: An Introduction to ATM-Based Networks. Reading, Mass.: Addison-Wesley, 1991.

Heinanen, J. Multiprotocol Encapsulation over ATM Adaptation Layer 5. RFC 1483. Network Working Group. July 1993.

ITU-T. B- ISDN -- ATM Adaptation Layer -- Service Speci f ic Co nnec tion Orie nted Protocol (SSCOP). Final Draft. March 10, 1994.

Laubach, M. Classical IP and ARP over ATM. RFC 1577. Network Working Group. January 1994.

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Where to Go Next

Use the following table to determine where to go next.

If you want to Go to

Learn about MPLS concepts. Chapter 2 Start ATM or MPLS. Chapter 3 Change default settings for ATM interface

parameters. Change default settings for ATM signaling

parameters. Change default settings for ATM PVC service record

and PVC parameters. Change default settings for classical IP service

record parameters. Change default settings for LAN Emulation client

service record parameters. Change default settings for Multi-Protocol over ATM

server parameters. Change default settings for the ATM router

redundancy parameter. Change default settings for MPLS parameters. Chapter 11 Obtain information about Site Manager parameters. Appendix A Monitor ATM using the BCC show commands. Appendix B Configure NHRP for MPOA services. Appendix C

Understanding ATM, MPOA, ATM Router Redundancy, and OAM

Chapter 4

Chapter 5

Chapter 6

Chapter 7

Chapter 8

Chapter 9

Chapter 10

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Chapter 2

Understanding MPLS

This chapter desc ribes th e conce pts un derlyi ng MPLS and, where a ppropr iate, th e specific ways Bay Networks implements these concepts on its routers. It contains the following information:

Topic Page

MPLS General Information 2-2 The MPLS Network 2-5 Supported Proto cols 2-7 For More Information 2-7 Where to Go Next 2-8

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Configuring ATM and MPLS Services

MPLS General Information

Multiprotocol Label Switching (MPLS) is an emerging Internet Engineering T ask Force (IETF) sta ndard that i s currentl y in draft fo rm. Its pr imary goal is to provi de a standardized solution that superce des existing proprietary solutions for integrating label-swapping and forwarding with ne twork layer routing. MPLS works in an environment where traditional network layer routing protocols (for example, OSPF and BGP) are used to maintain the routing topology and forwarding in formation base (FIB) for each router.

In connectionless networks (those using connectionless network layer protocols), as a packet travels from one hop to another, each router must determine where to forward the packet based on the individual packet header. This decision process can be broken down into two major tasks: classifying a set of packets as part of a forwarding equivalence class (FEC) and mapping each FEC to a next hop.

By classifying a set of packets as part of an FEC, the router uses the same forwarding criter ia for each packet. All packets that belong to a particular FEC and that trav el from a particular node foll ow the same path. This group of packets is called a “stream.” A packet stream is a group of packets that follows the same path to a destination. I n a con v ention al IP netw ork, each ro uter hop e xamines ea ch packet to determine its destination.

2-2

Using MPLS, the examination of the packet is done only once. The first router assigns a label that defines the specific packet stream. Each intervening router then forward s packets ba sed on the fixed-length labels. Labels reside in the label information base (LIB), which contains both inbound and outbound labels associated with inbound and outbound interfaces.

Looking up a label is faster than interpreting the destination of an individual packet and routing data based on that destination. By assigning labels to packets or packet streams, the transmission speed of your network increases.

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MPLS System Overview

The Bay Networks MPLS implementation consists of three major components :

• Label distribution entity

• MPLS label management (MLM) entity

• Forwarding entity

Understanding MPLS

Other

interfaces

Figure 2-1

OSPF/RIP

Forwarding

illustrates the basic MPLS system architec tur e.

Routing

table

LDP

MLM

Driver

Key

MIB

External component

MPLS component

Data path Control path

Figure 2-1. The MPLS System

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ATM0058A

2-3

Configuring ATM and MPLS Services

Label Distribution Entity

The label dis tribution entity is essentially the implementation of the label distribution protocol (LDP). LDP is the set of procedures and messages by which

label-switching routers (LSRs) establish label-switched paths (LSPs) through a network. LDP establishes these paths by mapping network layer routing information directly to data link layer switched paths.

LDP associates a packet stream with a specific LSP and assign the LSP a specific label. The label infor mation is distributed betwe en the LSRs and LERs to maintain stream mapping information.

MPLS Label Management

The MPLS label management (MLM) entity communicates with LDP. It is responsible for:

• Establishing the default VC (0/32)

• Responding to requests from LDP (for example, requests for a label and

establishing VC communications)

Forwarding

2-4

• Communicating with the ATM driver to set up and tear down VCs

The forwarding entity encapsulates and decapsulates the data that it sends and receives over the MPLS interface.

Outbound data is delivered to the encapsulation process by the higher layers and delivered to the lower-level driver for transmission to the MPLS network.

Inbound data is received from the MPLS network by the lower-level driver and delivered to the decapsulation process, where it is stripped of layer 2 protocol headers. The decapsulation process then passes the inbound data to higher layers for further processi ng.

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The MPLS Network

The MPLS network (Figure 2-2) consists of two major components:

• Label switching router (LSR)

• Label edge router (LER)

Understanding MPLS

100BASE-T

10BASE-T

LER

MPLS network

LER

100BASE-T

LSR

LER

LSR

100BASE-T

LER

Key

Label-switching router (LSR)

Label edge router (LER)

Virtual connection

10BASE-T

100BASE-T

Figure 2-2. Sample MPLS Network

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ATM0057A

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Configuring ATM and MPLS Services

Label Switching Router

A label-switching router (LSR) is a router that contains all label- switching interfaces. The LSR controls MPLS forwarding in the MPLS network. An LSR performs table lookup on received packets and, based on the packet label, forwards the packet or packet stream to the specified outgoing inter f a ce. The LSR swaps the labels of the packet headers before transmitting the packets to the MPLS network.

Note:

An ATM LSR currently consists of an ATM switching device th at works in conjunction with a UNIX Ultrasparc workstation running Solaris and LDP. For information about how to configure an ATM LSR, refer to the documentation provided with your switching device.

Label Edge Router

A label edge router (LER) is an LSR that resides between the IP and MPLS networks. This router performs two generalized functions:

• It receives non-MPLS traffic, labels that traffic, and forwards it to another

label-switching interface.

2-6

• It receives labeled MPLS traffic, strips the label from the packets, and

forwards the traffic over a non-MPLS interface.

Note:

This guide describes how to configure the LER. For information about how to start MPLS on the router, see “Starting MPLS” on page 3-30. For information about how to customize the ATM router interface for MPLS, see Chapter 11, “Customizing MPLS Confi gur ation.”

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Supported Protocols

MPLS supports the following protocols:

•IP

•RIP

• BGP

• OSPF

For More Information

For more information about MPLS, refer to the following documents: Black, D. Switching Solutions Expanding Networks. Draft document. Expected

publication date, 1999. “LDP Specification,” Andersson, Doolan, Feldman, Fredette, Thomas, work in

progress, Internet Draft <draft-ietf-mpls-ldp-01.txt>. August, 1998.

Understanding MPLS

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“Multiprotocol Label Switching Arc hitecture,” Callon, Rosen, Viswanathan, w ork in progress, Internet Draft <draft-ietf-mpls-arch-01.txt>. March, 1998.

2-7

Configuring ATM and MPLS Services

Where to Go Next

Use the following table to determine where to go next.

If you want to Go to

Learn about ATM concepts. Chapter 1 Start ATM or MPLS. Chapter 3 Change default settings for ATM interface

parameters. Change default settings for ATM signaling

parameters. Change default settings for ATM PVC service record

and PVC parameters. Change default settings for classical IP service

record parameters. Change default settings for LAN Emulation client

service record parameters. Change default settings for Multi-Protocol over ATM

server parameters. Change default settings for the ATM router

Chapter 4

Chapter 5

Chapter 6

Chapter 7

Chapter 8

Chapter 9

Chapter 10

2-8

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Chapter 3

Starting ATM, ATM MPOA Ser ver,

ATM Router Redundancy, and MPLS

This chapter describes how to create a basic ATM or MPLS configuration by specifying v alues for requir ed parameter s only and accep ting def ault v alues for all other parameters. This chapter contains the following information:

Topic Page

Starting Configuration Tools 3-2 Starting ATM Services 3-2 Starting the MPOA Server 3-15 Starting ATM Router Redundancy 3-23 Deleting ATM from the Router 3-29 Starting MPLS 3-30 Deleting MPLS from the Interface 3-39 Where to Go Next 3-40

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For overview information about ATM, see Chapter 1, “Understanding ATM, MPOA, ATM Router Redundancy, and OAM.” For overview information about MPLS, see Chapter 2, “Understanding M PLS.”

3-1

Configuring ATM and MPLS Services

Starting Configuration Tools

Before configur ing ATM, refer to the following us er guides for instructions on how to start and use the Bay Networks configuration tool of your choice.

Configuration Tool User Guide

Bay Command Console (BCC) Site Manager

Starting ATM Services

You can use the BCC or Site Manager to start ATM on the router using default values for all parameters.

Using the BCC

To start ATM on a router using the BCC:

Add ATM to the configuration.

Enable ATM signaling (if you plan to define either a LANE or classical IP service record).

Define an ATM service record.

If you defined a PVC service record, add at least one virtual circuit to that service record.

Enable protocols on the ATM service record.

Using the Bay Command Console Configuring and Managing Routers with

Site Manager

3-2

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Adding ATM to the Configuration

To add ATM to the configuration, navigate to the top-level prompt and enter:

atm slot

<connector_number>

<slot_number>

[

module

<module_number>

]

connector

slot_number module_number

is the number of the chassis slot containing the link module.

is a convention used for other routers within the System 5000

chassis. You need only enter a module number when configuring an ATM router in the System 5000 chassis (that is, the Model 5782 Centillion Multiprotocol Engine). The module number for the ATM router is always 1.

connector_number

The top-level prompt for BCC configuration on the System 5000

Note:

is the number of a connector on the link module.

platform is “stack.” However, the remainder of this guide uses the “box” prompt associated with the BN platform in its examples.

For example, the following command adds ATM to the BN configurat ion on slot 5, connector 1:

box#

atm slot 5 connector 1

atm/5/1#

Enabling Signaling (LANE and Classical IP Service Records Onl y)

To enable signaling on an ATM interface, navigate to the ATM prompt and enter:

signaling

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For example, the following command enables signaling on slot 5, connector 1:

atm/5/1# signaling/5/1#

signaling

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Configuring ATM and MPLS Services

Defining an ATM Service Record

Using the BCC, you can define PVC, classical IP, and LANE service records.

Defining PVC Service

To define a PVC servi ce record, navigate to the ATM interface prompt and enter:

pvc-service

service_name encapsulation_type

<service_name>

is a unique text string that you assign to the service record.

encapsulation

is the data encapsulation type that you wa nt the PVC service

<encapsulation_type>

record to use. For exampl e, the foll o w ing comman d def i nes a PVC servi ce recor d with the na me

“boston” on ATM slot 5, connector 1:

atm/5/1# pvc-service/boston#

Note:

pvc-service boston encapsulation llc-snap

You must add at least one PVC to a PVC ser vi ce r ecord. Go to “Addi ng PVCs” on page 3-5 for instructions.

Defining Classical IP Service

To define a classical IP service record, navigate to the ATM interface prompt and enter:

classical-ip-service

<service_name>

encapsulation

<encapsulation_type>

3-4

service_name encapsulation_type

is a unique text string that you assign to the service record.

is the data encapsulation type that you wa nt the classical IP

service record to use. For examp le, the follo wing command def ines a cl assical IP serv ice record with the

name “dallas” on ATM slot 5, connector 1:

atm/5/1# classical-ip-service/dallas#

classical-ip-service dallas encapsulation llc-snap

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Defining LEC Service

To define a LAN emulation client (LEC) service record, navigate to the ATM interface prompt and enter:

lec-service

service_ nam e encapsulation_type

encapsulation

<encapsulation_type>

is a unique text string that you assign to the service record.

is the data encapsulation type that you wa nt the LEC service

record to use. For example , the fo llowing command defines a LEC service rec ord with the name

“newyork” on ATM slot 5, connector 1:

atm/5/1# lec-service newyork encapsulation lec lec-service/newyork#

Adding PVCs

You must add at least one PVC to a PVC service record for that service record to operate. A PVC is defined by its VPI/VCI pair.

A virtual path is a set of virtual channels between a common source and destination. The virtual channels within a virtual path logically associate with a common iden tifier. This identifier is called the virtual path identifier (VPI) and is part of the cell header.

A virtual channel is a logical connection between two communicating ATM entities. Each virtual channel can carry a different protocol or traffic type. The virtual channel transports cells that have a common identifier. The identifier is called the virtual channel identifier (VCI) and is part of the cell header.

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Note:

ATM does not allow duplicate VPI/VCI pairs on the same physical interface (tha t is, on the same li nk module ). However, dupli cate VPI /VCI pair s can exist on different physical interfaces (that is, on different link modules).

3-5

Configuring ATM and MPLS Services

To add a PVC to a PVC service record, navigate to the ATM PVC service prompt and enter:

pvc vpi

vpi_number

<vpi_number>

identifies the virtual path of the PVC. The header can contain a

<vci_number>

vci

maximum of 8 VPI bits for a UNI connection. This bit range allows for path identifiers from 0 to 255.

vci_number

identifies the virtual channel of the PVC. The header can contain a

maximum of 16 VCI bits. This bit range allows for channel identifiers from 32 to

65535.

Note:

Following the recommendation of the ATM Forum, virtual channel identifiers from 0 to 31 are reserved for signaling and added functionality.

For example, the following command adds PVC 0/130 to the configuration on PVC service record boston:

pvc-service/boston# pvc vpi 0 vci 130 pvc/0/130#

Adding Protocols to an ATM Service Record

The BCC currently supports only IP and IPX configuration over ATM. Table 3-1 indicates which service records support the IP and IPX protocols.

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Table 3-1. Service Record Protocol Support

Service Record Type IP IPX

pvc-service classical-ip-service lec-service

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Adding IP

To add IP to a service record, navigate to the ATM service record prom pt (for classical IP or LEC service records), or the ATM PVC to which you want to add IP, and enter:

ip address

address

and

mask

are a v alid IP address an d its a ssociate d subnet mask, e xpressed

mask

<mask>

in either dotted-decimal notation or in bit notation. For example, the following command configures an IP address of 2.2.2.2 and a

subnet mask of 255.255.255.0 on ATM PVC 0/130:

pvc/0/130# ip address 2.2.2.2 mask 255.255.255.0 ip/2.2.2.2/255.255.255.0#

Adding IPX

To add IPX to a service record, navigate to the ATM service record prompt (for LEC service records), or the ATM PVC to which you want to add IPX, and enter:

ipx address

address

is a valid IPX address expressed in either dotted-decimal notation or in

bit notation. For example, the following command configures an IPX address of 0000001a on

ATM PVC 0/130:

pvc/0/130# ipx address 0000001a ipx/0000001a#

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Configuring ATM and MPLS Services

Using Site Manager

To start ATM on a router using Site Manager:

Create an ATM circuit.

Define an ATM service record.

Enable protocols on the ATM service record.

If you defined a PVC service record, add at least one virtual circuit to that service record.

Creating an ATM Circuit

To create an ATM circuit, complete the following tasks:

You do this System responds

Site Manager Procedure

1. In the Configuration Manager window, click on an ATM link module interface (

ATM1

2. Click on OK to accept the default circuit name.

3. Click on

4. Click on OK to accept the default settings. The Edit ATM Connector window opens.

5. Go to the next section to define a service record on the circuit.

Note:

Accepting the defaults in the Initial ATM Signaling Config window

. The Initial ATM Signaling Config window

ATM

The Add Circuit window opens.

The Select Connection Type window opens.

opens.

enables signaling on the interface. If you are running only PVCs on the interface, you do not need signaling enabled.

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Defining an ATM Service Record

The Configuration Manager allows you to define service records for a specific data encapsulation type. Depending on the data encapsulation type you choose, the Configuration Manager also allows you to select a PVC or SVC connection type for that service record.

Caution:

You cannot edit the Data Encapsulation Type or Virtual Connection Type parameters after you assign them to a service record. However, you can edit the Data Encapsulation Type for individual PVCs.

Table 3-2

identifies which data encapsulation types you can apply to permanent and switched virtual circuits. For an explanation of the different data encapsulation types, and rules for assigning data encapsulati on, see Chapter 1, “Understanding ATM, MPOA, ATM Router Redundancy, and OAM.”

Table 3-2. Valid Data Encapsulation Types for PVCs and SVCs

Data Encapsulation Type Permanent Virtual Circuit Switched Virtual Circuit

LANE LLC/SNAP NLPID NULL

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Configuring ATM and MPLS Services

Adding a Service Record for PVCs

Note: The values for some parameters are contingent on the va lues of others.

If you change one parameter, you must press the Enter or Tab key to advance from one parameter cell to another. Pressing either key acknowledges any changes to a parameter. If you neglect this step, the Configuration Manager may not provide the appropriate option for other parameters.

To add a service record for PVCs, complete the following tasks:

You do this System responds

Site Manager Procedure

1. In the Configuration Manager window, click on an ATM link module interface (

ATM1

2. Click on

3. Click on

4. Click on

5. Set the parameter to Click on description on page A-16.

6. Press the the Virtual Con nection Type parameter.

7. Change the parameter to the parameter description on page A-16.

8. Click on OK. The Select Protocols window opens.

9. Go to “Enabling Protocols on an ATM

Service Record” on page 3-12.

. The Edit ATM Connector window opens.

ATM Service Attributes

. The ATM Service Record Parameters

Add

Data Encapsulation Type

LLC/SNAP, NLPID

or see the parameter

Help

Enter

Tab

Virtual Connection Type

. Click on

PVC

. The ATM Se rvice Records List w indow

, or

NULL

key to advance to

or see

Help

The Select Connection Type window opens.

opens.

window opens.

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Adding a Service Record for Classical IP

To add a service record for classical IP, complete the following tasks:

Site Manager Procedure

You do this System responds

1. In the Configuration Manager window, click on an ATM link module interface (

ATM1

2. Click on

3. Click on

4. Click on

5. Set the parameter to on

Help

on page A-16.

6. Click on OK. The Select Protocols window opens.

7. Go to “Enabling Protocols on an ATM

Service Record” on page 3-12.

. The Edit ATM Connector window opens.

ATM Service Attributes

. The ATM Service Record Parameters

Add

Data Encapsulation Type

LLC/SNAP

or see the parameter description

. The ATM Se rvice Records List w indow

NULL

. Click

The Select Connection Type window opens.

opens.

window opens.

Adding a Service Record for LANE

To ad d a service record for LANE, complete the following tasks:

Site Manager Procedure

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You do this System responds

1. In the Configuration Manager window, click on an ATM link module interface (

ATM1

2. Click on

3. Click on

4. Click on

. The Edit ATM Connector window opens.

ATM Service Attributes

. The ATM Service Record Parameters

Add

. The ATM Se rvice Records List w indow

The Select Connection Type window opens.

opens.

window opens.

(continued)

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Configuring ATM and MPLS Services

Site Manager Procedure

You do this System responds

5. Click on OK. The Select Protocols window opens.

6. Go to the next section, “Enab ling Protocols

on an ATM Service Record.”

(continued)

Enabling Protocols on an ATM Ser vice Record

Depending on the data encapsulation type and virtual connection type (PVC or SVC) that you choose for the service reco rd, the ro ute r supports various protocols.

You can select and configure protocols immediately after you create a service record, or you can exit the Select Protocols window and add protocols at a later time.

Adding Protocols Immediately After Creating a Service Record

To add protocols to a service record immediately after creating it, complete the following tasks:

Site Manager Procedure

3-12

You do this System responds

1. In the Select Protocols window, click on the protocols you want to add.

2. Click on OK. For each protocol you select, the

A check mark appears in the bo x f or each protocol that you select.

Configuration Manager displays a protocol-specific window prompting you for required information.

Click on the appropriate protocol-specific guide.

for any parameter, or see

Help

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Adding Protocols to an Exis ting Service Record

To add protocols to an existing service record, complete the following tasks:

Site Manager Procedure

You do this System responds

1. In the Configuration Manager window, click on an ATM link module interface (

ATM1

2. Click on

3. Click on

4. Click on the servi c e record to which you want to add protocols.

5. Click on

6. Choose

7. Click on the protocols that you want to add.

8. Click on OK. For each protocol you select, the

. The Edit ATM Connector window opens.

ATM Service Attributes

Protocols

Add/Delete

. The Protocols menu opens.

. The Select Protocols window opens.

. The ATM Se rvice Records List w indow

The Select Connection Type window opens.

opens. The Protocols menu selection becomes

active.

A check mark appears in the box for each protocol that you select.

Configuration Manager displays a protocol-specific window prompting you for required information.

Click on the appropriate protocol-specific guide.

for any parameter, or see

Help

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Configuring ATM and MPLS Services

Adding PVCs

You must add at least one virtual circuit to a PVC service record for that service record to operate. When you finish configuring the protocols for a PVC service record, the ATM Virtual Channel Li nk window opens.

To add a PVC to a PVC service record, complete the following tasks:

You do this System responds

Site Manager Procedure

1. In the Configuration Manager window, click on an ATM link module interface (

ATM1

2. Click on

3. Click on

4. Click on the PVC service record to which you want to add a virtual circuit.

5. Click on

6. Click on

7. Set the

or see the parameter description on

Help

page A-21.

8. Set the

or see the parameter description on

Help

page A-22.

9. Click on OK. You return to the ATM Virtual Channel

10. Click on

11. Click on

12. Click on

13. Click on

. The Edit ATM Connector window opens.

ATM Service Attributes

. The ATM Virtual Channel Link window

PVC

. The ATM Virtual Channel Link

Add

VPI Number

VCI Number

. You return to the ATM Service Records

Done

. You return to the Edit ATM Connector

Done

. You return to the Select Connection Type

Done

. You return to the Configuration Manager

Done

. The ATM Se rvice Records List w indow

parameter. Click on

The Select Connection Type window opens.

opens.

Parameters window opens.

Link window.

List window.

window.

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117374-C Rev 00

Avaya ATM, MPLS User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Configuring ATM and MPLS Services

Contents

Figures

Tables

Preface

Before You Begin

Text Conventions

Acronyms

Bay Networks Technical Publications

How to Get Help

ATM General Information

ATM Cells

Cell Header

Cell Information Field

Data Transmission

Permanent and Switched Virtual Connections

ATM Layers

Physical Layer

ATM Layer

ATM Adaptation Layer

Service Records and Virtual Circuits

Supported Protocols

Things to Remember

Rules for Editing Protocols

Data Encapsulation Methods

LANE Encapsulation

LLC/SNAP Encapsulation

NULL Encapsulation

NLPID Encapsulation

Selecting a Data Encapsulation Method

Selecting LLC/SNAP Encapsulation

Selecting NULL Encapsulation (VC-Based Multiplexing)

Encapsulation Rules for PVCs

PVC Access Methods

Multiple PVCs

One PVC

Hybrid Access PVCs

Using Hybrid PVCs for Transparent Bridging

SVC Access Methods

Assigning ATM Addresses

Entering an ATM Address Network Prefix

Entering an ATM Address User Part

ATM Traffic Parameters

Using the PCR

Using the SCR

Using the MBS

ARP and Inverse ARP Support

ATM Error Checking

Simulated Multicast Packet Support

Converting Mb/s to Cells/s

Classical IP over ATM Concepts

ATM Address Resolution

Configuring an ATM Service Record for ATMARP

Configuring an ATM Address for an Adjacent Host

ATM LAN Emulation Concepts

LAN Emulation Connectivity

LAN Emulation Components

LAN Emulation Configuration Server

LAN Emulation Clients

LAN Emulation Server

Broadcast and Unknown Server

Redundant LES/BUS

LAN Emulation States

Initial State

LECS Connect State

Configure State

Join State

Initial Registration Sta te

BUS Connect State

Operational State

Multi-Protocol over ATM Concepts

MPOA Logical Components

MPOA Basic Elements

Establishing a Network Cut-Through

ATM Router Redundancy Concepts

PVC Operations and Management Concepts