Avaya APPN User Manual

Configuring APPN Services

Router Software Version 10.0

Site Manager Software Version 4.0

Part No. 112908 Rev. A

January 1996

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(continued)

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About This Guide

Audience ..........................................................................................................................xiii

Before You Begin .............................................................................................................xiii

Bay Networks Customer Support ....................................................................................xiv

CompuServe .............................................................................................................xiv

InfoFACTS .................................................................................................................xv

World Wide Web ........................................................................................................ xv

How to Get Help .............................................................................................................. xv

Conventions .....................................................................................................................xvi

Ordering Bay Networks Publications ..............................................................................xvii

Acronyms ........................................................................................................................xvii

Chapter 1 Advanced Peer-to-Peer Networking Overview

APPN Networking Overview ...........................................................................................1-2

APPN Node Types ..........................................................................................................1-2

Network Nodes ........................................................................................................1-3

End Nodes ...............................................................................................................1-3

Low-Entry Networking Nodes ..................................................................................1-3

Control Points and Logical Units .....................................................................................1-5

Dependent Logical Unit Requester and Server ..............................................................1-6

lnterfaces, Ports, and Link Stations ................................................................................1-8

Interfaces .................................................................................................................1-9

Ports .........................................................................................................................1-9

Link Stations .............................................................................................................1-9

Connection Networks ...................................................................................................1-10

Intermediate Session Routing ......................................................................................1-12

Packet Segmentation and Reassembly .................................................................1-13

Adaptive Pacing .....................................................................................................1-13

High Performance Routing ...........................................................................................1-14

Rapid Transport Protocol .................................................................................1-16

Non-Disruptive Path Switching ........................................................................1-16

End-to-End Error Recovery .............................................................................1-17

End-to-End Flow and Congestion Control .......................................................1-17

Automatic Network Routing ....................................................................................1-18

Fast Packet Switching ......................................................................................1-18

Session Transparency .....................................................................................1-18

Source Routing ................................................................................................1-18

APPN Services .............................................................................................................1-19

Session Services ...................................................................................................1-19

Directory Services ..................................................................................................1-20

Topology and Routing Services .............................................................................1-20

Conﬁguration Services ...........................................................................................1-21

Management Services ...........................................................................................1-21

For More Information about APPN ...............................................................................1-22

Chapter 2 Enabling APPN Services

Using the Parameter Descriptions ..................................................................................2-1

Enabling APPN over LLC2 Interfaces .............................................................................2-2

Enabling APPN over LLC2 Interfaces Using SRB ..........................................................2-7

Enabling APPN Interfaces over SDLC ..........................................................................2-12

Chapter 3 Editing APPN Parameters

Using the Parameter Descriptions ..................................................................................3-1

Accessing APPN Parameters .........................................................................................3-2

Editing APPN Global Parameters ...................................................................................3-3

APPN Global Advanced Parameters ........................................................................3-5

Editing APPN lnterfaces and Ports ...............................................................................3-14

Deleting APPN Interfaces ......................................................................................3-16

Editing APPN Ports ................................................................................................3-17

Deleting APPN Ports ..............................................................................................3-19

Adding Ports to an APPN Interface ........................................................................3-19

Editing APPN Advanced Port Parameters .............................................................3-23

Editing APPN Adjacent Link Stations ...........................................................................3-33

Deleting Adjacent Link Stations .............................................................................3-40

Adding Adjacent Link Stations ...............................................................................3-41

Editing Advanced Adjacent Link Station Parameters .............................................3-47

Editing APPN Connection Networks .............................................................................3-55

Adding APPN Connection Networks ......................................................................3-57

Deleting APPN Connection Networks ....................................................................3-58

Editing APPN Connection Network Ports ...............................................................3-59

Adding APPN Connection Network Ports ..............................................................3-60

Deleting APPN Connection Network Ports ............................................................3-61

Editing APPN Advanced Connection Network Parameters ....................................3-61

Editing APPN Directory Entry Parameters ...................................................................3-66

Adding APPN LU Names to Directory Services .....................................................3-69

Deleting APPN Directory Entires ...........................................................................3-72

Appendix A APPN Base and Optional Function Sets

Appendix B APPN Default Settings

Index

vii

Figures

Figure 1-1. APPN Network with Different Node Types ...............................................1-4

Figure 1-2. CP-CP and LU-LU Sessions ....................................................................1-5

Figure 1-3. DLUR and DLUS in an APPN Network ....................................................1-7

Figure 1-4. Interface, Port, and Link Station Relationship ..........................................1-8

Figure 1-5. Sample APPN Connection Network ......................................................1-11

Figure 1-6. Nonadjacent LU-LU Session through an Intermediate Node .................1-12

Figure 1-7. APPN ISR Routing Functions in SNA Architecture ................................1-13

Figure 1-8. APPN HPR Routing Functions in SNA Architecture ..............................1-15

Figure 1-9. HPR RTP Connection Supporting APPN Sessions ...............................1-16

Figure 1-10. HPR ANR Routing and Packet Handling Operations .............................1-19

Figure 2-1. Source Route Encapsulation Dialogue Box .............................................2-3

Figure 2-2. APPN Local Node Name Conﬁguration Window .....................................2-3

Figure 2-3. APPN/FR Conﬁguration Window .............................................................2-5

Figure 2-4. Adjacent Link Station Dialogue Box .........................................................2-6

Figure 2-5. Source Route Encapsulation Dialogue Box .............................................2-7

Figure 2-6. Source Routing Global Parameters Window ............................................2-8

Figure 2-7. Edit SR Interface Window ......................................................................2-10

Figure 2-8. APPN Virtual Ring Number Conﬁguration Window ................................2-11

Figure 2-9. SDLC Line Parameters Window ............................................................2-13

Figure 2-10. Select Protocols Window .......................................................................2-15

Figure 2-11. APPN Local Node Name Conﬁguration Window ...................................2-16

Figure 2-12. APPN SDLC Address Conﬁguration Window ........................................2-17

Figure 2-13. Adjacent Link Station Dialogue Box .......................................................2-18

Figure 3-1. Conﬁguration Manager Window ...............................................................3-2

Figure 3-2. Edit APPN Global Parameters Window ...................................................3-3

Figure 3-3. Advanced APPN Global Parameters Window ..........................................3-6

Figure 3-4. APPN Interface List Window ..................................................................3-15

Figure 3-5. APPN Port List Window .........................................................................3-17

Figure 3-6. APPN/FR Port Conﬁguration Window ....................................................3-20

Figure 3-7. APPN Port Window ................................................................................3-23

Figure 3-8. APPN Adjacent Link Station List Window ..............................................3-33

Figure 3-9. APPN Adjacent Link Station Port Conﬁguration Window .......................3-41

Figure 3-10. APPN Adjacent Link Station Conﬁguration Window ..............................3-42

Figure 3-11. APPN Adjacent Link Station Advanced Conﬁguration Window .............3-48

Figure 3-12. APPN Connection Network List Window ...............................................3-56

Figure 3-13. Connection Network Conﬁguration Window ...........................................3-57

Figure 3-14. APPN Connection Network Port List Window ........................................3-59

Figure 3-15. Connection Network Port Conﬁguration Window ...................................3-60

Figure 3-16. APPN Connection Network Advanced Parameters Window ..................3-62

Figure 3-17. APPN Directory Entry List Window ........................................................3-67

Figure 3-18. Directory Entry Conﬁguration Window ...................................................3-69

Tables

Table 3-1. Link Activation Limit Default Values .......................................................3-26

Table A-1. APPN Base Function Sets ...................................................................... A-1

Table A-2. APPN Optional Function Sets ................................................................. A-4

Table B-1. APPN Global and Advanced Global Parameters .................................... B-1

Table B-2. APPN Interface and Port Parameters ..................................................... B-2

Table B-3. APPN Adjacent Link Station Parameters ................................................ B-4

Table B-4. APPN Connection Networks and Port Parameters ................................. B-5

Table B-5. APPN Directory Services Parameters .................................................... B-6

About This Guide

This guide describes how to customize Bay Networks™ router software for Advanced Peer-to-Peer Networking (APPN) services. Refer to this guide for

• An overview of APPN, as implemented on Bay Networks routers and Site Manager software (see Chapter 1)

• Instructions on enabling APPN services using Site Manager (see Chapter 2)

• Instructions on conﬁguring APPN parameters using Conﬁguration Manager software (see Chapter 3)

• APPN base and optional function sets Bay Networks supports (see Appendix A)

• A list of APPN parameters and their default settings in the Conﬁguration Manager (see Appendix B)

Audience

Written for system and network managers, this guide describes how to conﬁgure the Bay Networks implementation of APPN to suit your environment.

Before Y ou Begin

Before using this guide, you must complete the following procedures:

• Open a conﬁguration ﬁle

• Specify the router hardware, if this is a local-mode conﬁguration ﬁle

• Select the link- or net-module connector on which you are enabling APPN

Refer to

Conﬁguring Routers

for instructions.

xiii

Configuring APPN Services

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CompuServe

xiv

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About This Guide

(44) 272-760681.

Representative No. 591, or consult your listings for an ofﬁce near you.

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For additional information or advice, contact the Bay Networks Technical Response Center in your area:

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Configuring APPN Services

Conventions

This section describes the conventions used in this guide. angle brackets (< >) Indicate that you choose the text to enter based on the

arrow character (➔) Separates menu and option names in instructions.

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

192.32.10.12

Example: Protocols

<ip_address>

➔

AppleTalk identiﬁes the

, you enter

ping

AppleTalk option in the Protocols menu.

ping

bold text

Indicates text that you need to enter and command

dinfo

names in text. Example: Use the

command.

brackets ([ ]) Indicate optional elements. You can choose none, one,

or all of the options.

italic text

Indicates variable values in command syntax descriptions, new terms, ﬁle and directory names, and book titles.

quotation marks (“ ”) Indicate the title of a chapter or section within a book.

screen text

Indicates data that appears on the screen. Example:

Bay Networks Trap Monitor Filters

Set

vertical line (|) Indicates that you enter only one of the parts of the

command. The vertical line separates choices. Do not type the vertical line when entering the command.

Example: If the command syntax is

show at routes show at routes

nets

, you enter either

show at nets

, but not both.

xvi

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To purchase additional copies of this document or other Bay Networks publications, order by part number from Bay Networks Press™ at the following numbers. You may also request a free catalog of Bay Networks Press product publications.

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Acronyms

ANR Automatic Network Routing APPN Advanced Peer-to-Peer Networking COS class of service CP control point DLC data link control DLCI data link connection identiﬁer DLSw data link switching DLUR dependent logical unit requester DLUS dependent logical unit server DS directory services DSPU down stream physical unit EN end node EP entry point FDDI Fiber Distributed Data Interface FQPCID fully qualiﬁed procedure correlation identiﬁer GDS general data stream HPR High Performance Routing IP Internet Protocol ISR intermediate session routing LAN local area network LEN low-entry networking LLC logical link control

About This Guide

xvii

Configuring APPN Services

LU logical unit MAC media access control MDS multiple domain support MIB Management Information Base NCP Network Control Program NN network node NNS network node server PCID procedure correlation identiﬁer PU physical unit RSCV route selection control vector RTP Rapid Transport Protocol SAP service access point SATF shared access transport facility SDLC Synchronous Data Link Control SNA Systems Network Architecture SNMP Simple Network Management Protocol SSCP system services control point SRB source routing bridge TG transmission group TPF transmission priority ﬁeld VRN virtual routing node VTAM Virtual T ecommunications Access Method XID exchange identiﬁcation

xviii

Chapter 1

Advanced Peer-to-Peer Networking Overview

IBM Advanced Peer-to-Peer Networking (APPN) architecture concepts include

• APPN node types

• Control points and logical units

• Dependent logical unit requester and server

• APPN interfaces, ports, and link stations

• Connection networks

• Intermediate session routing

• High performance routing

• APPN services

Review these concepts if you are responsible for conﬁguring APPN on Bay Networks routers in your network, or if already familiar with APPN concepts, go directly to Chapter 2 for information on starting APPN started on a router.

1-1

Configuring APPN Services

APPN Networking Overview

APPN is an architectural extension of IBM Systems Network Architecture (SN A). As participants in an SNA network, APPN nodes use distributed network services for dynamic routing, connection, topology , and directory information, simplifying network deﬁnition and maintenance.

Bay Networks routers participate as APPN network nodes in IBM SNA network environments (with or without the presence of an IBM mainframe computer) and communicate with adjacent network nodes, end nodes, and low-entry networking nodes. APPN runs on all Bay Netw orks router platforms using local and wide area network facilities, as follows:

• LLC2 media, including Ethernet, Token Ring, and Frame Relay

• LLC2 using Source Routing Bridge (SRB) encapsulation formats over Ethernet, FDDI, SMDS, Frame Relay, and Point-to-Point (PPP) protocols

• SDLC links in point-to-point and multipoint conﬁgurations

The Bay Networks APPN implementation complies with Version 2 of the IBM APPN Network Node speciﬁcation, with advanced optional APPN function sets.

APPN Node Types

1-2

APPN supports the following node types:

• Network nodes

• End nodes

• Low-entry networking nodes

Network Nodes

Network nodes (NNs) provide routing and networking services to other network nodes and end nodes. These services include locating network resources, calculating routes, and routing sessions. NNs use conﬁgured or dynamic control-point-to-control-point (CP-CP) sessions with adjacent nodes to manage, communicate, and exchange network topology and resource information. Any adjacent node that does not support control point sessions (such as a low-entry networking node) cannot participate in this exchange and must rely on static deﬁnitions. An NN that provides control point services to end nodes is called a network node server (NNS).

End Nodes

End nodes (ENs) have control points that allow them to re gister and share network information (using CP-CP sessions) with the NNS. End nodes provide APPN services to local users and applications and can operate independently in simple network conﬁgurations. In most conﬁgurations, end nodes are application hosts and workstations that register their resources with their network node server.

Advanced Peer-to-Peer Networking Overview

Low-Entry Networking Nodes

Low-entry networking nodes (LENs) are the simplest type of node in an APPN network. LEN nodes communicate with each other as adjacent peers.

LENs do not use control point sessions and cannot exchange resource information with an NN. Therefore, the resource information for LENs is preconﬁgured and supported at the NN. LENs typically include personal computers and workstations.

igure 1-1 illustrates a simple APPN network with the three APPN node types.

1-3

Configuring APPN Services

Low-entry networking

node (LEN)

APPN network node

(NN)

AS/400 end node

(EN)

Low-entry networking

node (LEN)

Figure 1-1. APPN Network with Different Node Types

1-4

Control Points and Logical Units

APPN uses control points (CPs) to manage nodes and network resources by establishing CP-CP sessions between nodes. All CP-CP sessions use logical unit (LU) 6.2 sessions.

Advanced Peer-to-Peer Networking Overview

During a CP-CP session (F information. Network nodes use CP-CP sessions to keep track of the network topology and directory information. Adjacent end nodes use CP-CP sessions to register resources and to request directory searches from the NNS.

Network node

APPN.A

CP-CP, LU-LU sessions

Figure 1-2. CP-CP and LU-LU Sessions

Network node

igure 1-2), adjacent nodes exchange network

End node

APPN.C

APPN.B

CP-CP, LU-LU sessions

In Figure 1-2, APPN.C registers its local resources with APPN.B, and sends requests to APPN.B for information about the netw ork and its resources. APPN.B functions as an NNS for APPN.C.

APPN.B has CP-CP sessions with both APPN.A and APPN.C. In this example, APPN.A and APPN.B exchange network topology and cooperate in directory searches.

1-5

Configuring APPN Services

Dependent Logical Unit Requester and Server

APPN’s Dependent Logical Unit Requester (DLUR) supports LU type 0,1,2,3 and LU6.2 dependent logical units within APPN. In contrast to the base APPN architecture, which uses independent LUs for LU-to-LU sessions, dependent LUs need a mainframe-based system services control point (SSCP) to establish and manage LU-to-LU sessions. DLUR allows these dependent LUs to use APPN networks by encapsulating the SSCP control ﬂows within the APPN LU 6.2 sessions. The APPN network routes the dependent LU-LU data ﬂows.

DLUR works with the dependent LU server (DLUS) component of the virtual telecommunications access method (VTAM) to provide a path for SSCP ﬂows between VTAM and dependent LUs across an arbitrary APPN backbone network. The DLUR node serves as a point of connection for PU2.0 devices (such as 3270-type devices) to attach to an APPN backbone.

The DLUR and DLUS components in an APPN network allow the SSCP and the PU2.0 device to exchange control ﬂows across the APPN backbone. DLUR and DLUS form a tunnel (called a CP-SVR pipe) that allows the SSCP at the DLUS side of the pipe to send SNA control ﬂows to the PU2.0 device at the DLUR side of the pipe. The CP-SVR pipe is a pair of LU6.2 sessions that encapsulate the SSCP control ﬂows.

1-6

igure 1-3 illustrates the DLUR and DLUS components in APPN.

Advanced Peer-to-Peer Networking Overview

SSCP sessions

(encapsulated in

CP-SVR pipe

PU2.0

LU-LU sessions

(natively routed by

APPN network)

APPN network node

with DLUR

Figure 1-3. DLUR and DLUS in an APPN Network

Typically, in a large network, multiple DLUS nodes serve many DLUR nodes distributed across the APPN backbone. A DLUR node can establish pipes with several DLUS nodes, although a single PU2.0 de vice can recei v e traf ﬁc from only one of them, because the device is only controlled by a single SSCP.

When the SSCP and the PU2.0 device exchange control ﬂows, BINDs establish the path that the LU-LU session trafﬁc uses through the network. Since the BIND ﬂows independently of the CP-SVR pipe, the LU-LU trafﬁc can take a different path through the network (the DLUS calculates a route using the topology database and class of service [COS] deﬁnitions). Refer to the “APPN Services” section in this chapter for information on the topology database and COS deﬁnitions.

CP-SVR pipe

VTAM

with DLUS

APPN

backbone

VTAM

1-7

Configuring APPN Services

lnterfaces, Ports, and Link Stations

APPN conﬁgurations comprise interfaces, ports, and link stations. Figure 1-4 shows how interfaces, ports, and link stations in a simple APPN network relate.

Note:

In this manual, the term

control (DLC

) in IBM publications.

interface

has the same meaning as

data link

APPN.NNA

Interface E51,LLC2,DLC00001

PORT0001

Link Station 1

Link Station 2

Link Station 3

Figure 1-4. Interface, Port, and Link Station Relationship

APPN.ENA

APPN.ENB

APPN.LENC

1-8

Interfaces

Ports

Link Stations

Advanced Peer-to-Peer Networking Overview

Interfaces provide data link control (DLC) processes to ensure reliable deliv ery of information between adjacent stations using a speciﬁc data link protocol, such as LLC or SDLC.

Each APPN interface can support one or more ports. A system-assigned DLC number (such as DLC00008) identiﬁes APPN interfaces

on Bay Networks network nodes. For information on adding and enabling APPN interfaces on Bay Networks

network nodes, refer to Chapter 2.

A port provides a unique access point (such as a MAC/SAP address pair) used by the local Bay Networks network node. A port in an APPN network has a DLC process and a set of conﬁgurable parameters.

A link station is a logical connection between adjacent nodes. Link stations use ports to create this connection. Multiple link stations can exist on a single port, and multiple link stations can exist between the same two nodes. You can conﬁgure a link station entry , or APPN creates it dynamically when a remote node initiates a connection.

Note:

The term adjacent link stations to communicate. Within APPN, a link refers to a logical connection between two nodes. The term throughout this manual and has the same meaning as link.

Link stations have a set of conﬁgurable parameters, such as

• Link station name and the name of the adjacent node

• Adjacent link station role: primary, secondary, or negotiable

• Adjacent link station deﬁnitions, such as MAC and SAP addresses

link

often refers to the physical components that enable two

transmission group (TG)

is also used

1-9

Configuring APPN Services

Connection Networks

APPN end nodes on a shared access transport facility (SATF), such as a Token Ring network, are directly connected to each other; they can communicate with each other without having to route trafﬁc through an intermediate network node. However, these end nodes still require deﬁnitions to other nodes and the nodes must be accessible over CP-CP sessions. A APPN conﬁgurations by reducing the number of connections that you must conﬁgure between nodes on an SATF.

When two nodes on the same SATF exist on the same connection network, these nodes are unaware that they have a direct connection to each other; the NNS, acting as an APPN virtual routing node (VRN), calculates a route between the tw o end nodes so that they can communicate directly. For the end nodes to communicate with each other over a connection network, the end nodes require a connection to the VRN and a connection to the NNS.

igure 1-5 illustrates a sample connection network. This connection network,

such as that between EN2 and EN3, may use resources at the network node (NN1) to establish sessions with each other.

connection network

(CN) simpliﬁes

1-10

Advanced Peer-to-Peer Networking Overview

EN2 EN3

Traffic

SATF

Virtual Routing

Node

NN1 EN4

Figure 1-5. Sample APPN Connection Network

1-11

Configuring APPN Services

Intermediate Session Routing

Intermediate session routing (ISR) provides a reliable, connection-oriented, LU-LU session path between nonadjacent APPN nodes. ISR session connectors (SCs) and a session connection manager (SCM) forward sessions through the intermediate network node (F

At session endpoints, the LU, with control point services, establishes a session with a session partner and routes session data back and forth with the partner LU. INTERMEDIATE network nodes do not control the LU endpoints, and LU services cannot be invoked on these nodes. ISR forwards session data to the next node along the session path.

Intermediate

LU-A to LU-C

Session

Network Node B

igure 1-6).

End Node C

LU-C

NNB

Network Node A

LU-a

ISR Services

LU-A to LU-C

Session

Figure 1-6. Nonadjacent LU-LU Session through an Intermediate Node

In Figure 1-6, LU-A and LU-C are nonadjacent session partners. ISR at NNB forwards session data between the nonadjacent nodes, LU-A and LU-C. NNB creates a session connector (SC) for each session passing through it.

igure 1-7 illustrates ISR function placement in the SNA layered architecture.

Routing takes place at the SNA Layer 4, called the Transmission Control layer. Layer 4 performs ﬂow control operations, speciﬁcally segmentation and reassembly, and pacing.

1-12

+ 116 hidden pages

Avaya APPN User Manual

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