Wellink W202ER User Manual
VisionNet
VisionNet
VisionNetVisionNet
202ER ADSL Ethernet Router
User’s Manual
Revision 1.1
February 27, 2003
VisionNet 202ER ADSL Ethernet Router User’s Guide
Table of Contents
1 Introduction.......................................................... 9
2 Getting to Know the VisionNet 202ER ............. 11
Features..................................................................................9
System Requirements........................................................... 9
Using this Document............................................................10
Notational convention s.................................................10
Typographical conventions ..........................................10
Special messages.........................................................10
Parts Check..........................................................................11
Front Panel...........................................................................12
Rear Panel............................................................................13
3 Quick Start......................................................... 15
Part 1 — Connecti ng the Hardware....................................15
Step 1. Conne ct t he ADSL cable an d o pti onal
telephone. ..................................................................16
Step 2. Connect the Ethernet cable.............................17
Step 3. Attach the power connector. ...........................17
Step 4. Turn on the VisionNet 202ER and
power up your sy stems.............................................17
Part 2 — Configuring Your Computers ..............................18
Before you begin...........................................................18
Windows 95, 98 PCs:................................................18
Windows NT 4.0 workstations: ....................................19
Windows 2000 PCs:.....................................................20
Windows Me PCs .........................................................21
Assigning static Inte rnet info rmati on to your
PCs.............................................................................22
Part 3 — Configu ri ng th e V i sionN et 20 2ER………………23
Logging in to t he Vi sio nNe t 20 2ER Qui ck
Setup..........................................................................23
Operation Mode............................................................24
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VisionNet 202ER ADSL Ethernet Router User’s Guide
4 Getting Started with the Configuration
DNS Settings.................................................................24
PPP Settings .................................................................24
Default Router Settings ................................................25
Testing Your Installation......................................................26
Using VisionNet’s Diagnostic Utilities .................................27
Manager.......................................................... 29
Accessing the Configuration Manager ...............................29
Functional Layout.................................................................31
Commonly used buttons ..............................................31
The Home Tab and System View Table............................32
Changing the System Date and Time................................34
Changing the System Date and Time................................34
Changing Your Login Password.........................................35
Committing Your C hange s an d Reb ooting t he
Device................................................................................36
Committing your changes ............................................36
Rebooting the devi ce u si ng C on figur ati on
Manager.....................................................................37
5 Setting the LAN IP Address.............................. 39
Configuring the LAN IP Address.........................................39
6 Viewing System IP Information and
Performance Statistics ................................... 43
Viewing the VisionNet 202ER’s IP addresses...................43
Viewing IP Global Statistics.................................................44
7 Configuring Dynamic Host Configuration
iv
Protocol...........................................................45
Overview of DHCP...............................................................45
What is DHCP?.............................................................45
Why use DHCP?...........................................................45
VisionNet 202ER DHCP modes..................................46
VisionNet 202ER ADSL Ethernet Router User’s Guide
8 Configuring Network Address Translation........55
Configuring DHCP Server...................................................47
Viewing, modifying , a nd del eting ad d res s
pools, and excluding IP addresses from a
pool.............................................................................50
Viewing current DHCP address assignments ............50
Configuring DHCP Relay.....................................................52
Setting the DHCP Mode......................................................53
Overview of NAT..................................................................55
Your Default NAT Setup......................................................56
Viewing NAT Global Settings and Statistics .....................57
Viewing NAT Rules and Rule Statistics..............................60
Viewing Current NAT Translations .....................................61
Adding NAT Rules...............................................................63
The napt rule: Translatin g between p rivate and
public IP addresses...................................................63
The rdr rule: A llow ing e x te rnal a c ce ss to a
LAN computer............................................................65
The basic rule: Performing 1:1 translations................68
The filter rule: Configuring a basic rule with
additional criteria........................................................69
The bimap rule: Performing two-way
translations.................................................................71
The pass rule: Allowing specific addresses to
pass through untranslated........................................72
9 Configuring DNS Server Addresses................. 79
About DNS............................................................................79
Assigning DNS Addresses..................................................79
Configuring DNS Relay .......................................................74
10 Configuring IP Routes....................................... 77
Overview of IP Routes.........................................................77
Comparing IP routing to telephone switching.............77
Hops and gateway s......................................................78
Using IP routes to define default gateways.................78
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VisionNet 202ER ADSL Ethernet Router User’s Guide
11 Configuring the Routing Information
12 Configuring the ATM VCC ................................87
Do I need to define IP routes? .....................................78
Viewing the IP Routing Table..............................................79
Adding IP Routes.................................................................81
Protocol...........................................................89
RIP Overview.......................................................................89
When should you configure RIP?................................89
Configuring the VisionNet 202ER’s Interfaces with
RIP.....................................................................................84
Viewing RIP Statistics..........................................................86
Viewing Your ATM VC Setup..............................................87
Adding ATM VCs .................................................................88
Modifying ATM VCs.............................................................90
13 Configuring PPP Interfaces............................... 91
Viewing Your Current PPP Configuration..........................91
Viewing PPP Interface Details ............................................99
Adding a PPP Interface Definition ......................................96
Modifying and Deleting PPP Interfaces..............................97
14 Configuring EOA Interfaces.............................. 99
Overview of EOA..................................................................99
Viewing Your EOA Setup..................................................100
Adding EOA Interfaces......................................................102
15 Configuring IPoA Interfaces............................ 105
vi
Viewing Your IPoA Interface Setup ..................................105
Adding IPoA Interfaces......................................................106
16 Configuring Bridging........................................109
VisionNet 202ER ADSL Ethernet Router User’s Guide
17 Configuring Firewall Settings .......................... 113
18 Configuring IP Filters.......................................117
Overview of Bridges...........................................................109
Using the Bridging Feature................................................110
Defining Bridge Interfaces.................................................111
Deleting a Bridge Interface................................................112
Configuring Global Firewall Settings.................................113
Managing the Black List ....................................................116
Overview.............................................................................117
Viewing Your IP Filter Configuration.................................117
Configuring IP Filter Global Settings.................................118
Creating IP Filter Rules......................................................119
IP filter rule examples ........................................................124
Viewing IP Filter Statistics.................................................126
Managing Current IP Filter Sessions................................126
19 Viewing DSL Parameters................................129
A IP Addresses, Network Masks, and
Subnets.........................................................132
IP Addresses ......................................................................132
Structure of an IP address..........................................132
Network classes..........................................................133
Subnet masks.....................................................................133
B Binary Numbers............................................... 135
Binary Numbers .................................................................135
Bits and by tes..............................................................135
C Troubleshooting............................................... 137
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VisionNet 202ER ADSL Ethernet Router User’s Guide
Diagnosing Problem using IP Utilities...............................139
ping ..............................................................................139
nslookup ......................................................................140
D Glossary........................................................... 141
FCC Complia n ce Sta t em en t s
NOTE : This equipment has been tested and found to comply with the limits for a Class B
digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference in a residential installation. This
equipment generates, uses and can radiate radio frequency energy and, if not installed and
used in accordance with the instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference will not occur in a
particular installation. If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the equipment off and on, the
user is encouraged to try to correct the interference by one or more of the following
measures :
Reorient or relocate the receiving antenna
Increase the separation between the equipment and receiver.
Connect the equipment into an outlet on a circuit different from that to which the receiver is
connected.
Consult the dealer or an experienced radio/TV technician for help.
Warning : Modifications not expressly approved by the manufacturer could void the user’s
authority to operated the equipment under FCC rules
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VisionNet 202ER ADSL Ethernet Router User’s Guide
4 Getting S ta rted with the Configuratio n
Manager
The VisionNet 202ER in clude s p rein stalle d p rog ra m cal led the
Configuration Man age r, which provides an interface to the software
installed on the devi ce. I t ena ble s you to configure the devi ce
settings to meet the needs of your network. You access it through
your web browser from any PC connected to the Visi onNet 202E R
the LAN po rt .
via
This chapter describes how to use the Configuration Manager.
The VisionNet 20 2ER ma y al re ady be config u red to p r ovid e Inte rne t
connectivit y fo r you r ne two r k. If it w ork s p ro pe rly wi th t he
preconfigured settin g s, t hen yo u m a y not n eed to us e the
Note
Configuration Man ager. Cont act your ISP to dete rmine whi ch
settings you may ne ed to change , i f any.
Accessing the Configuration Manager
The Configurati on Man age r p r ogra m i s p rei n stal led in to me mory on
the VisionNet 202 ER . To a ccess t he p rogr a m, y ou need t he
following:
A PC o r lap top conne cted t o t he LA N p o rt on t he devi ce as
described in the Quick Start chapter.
An web browser installed on the PC. The program is
designed to wo r k be st wi th Mi cr o soft In te rn et E xplor e r®
version 5.0, Ne ts cape Navi ga to r® ve r sion 6.2 , o r lat er
versions.
You can access the program from any computer connected to the
VisionNet 202ER.
1. From a LAN computer, open your web browser, type the
following URL in the web address (or location) box, and
press <Enter>:
http://10.0.0.2
These are the predefined IP addresses for the LAN ports on the
VisionNet 202ER.
A login screen displays, as shown in Figur e 7 .
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VisionNet 202ER ADSL Ethernet Router User’s Guide
Figure 7. Login Screen
2. Enter your user name and password, and then click
3. The first time you launch the program, use these defaults:
.
Note
Default User Name:
Default Password :
admin
visionnet
You can change the password at an y time (see Chan ging You r
Login Password on p age 35 ). The u ser n ame cannot b e chang ed.
The System View p age displays each time you l aunch the
program (shown in Figure 8 on page 31).
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VisionNet 202ER ADSL Ethernet Router User’s Guid
Functional Layout
Configuration Man age r t a sks a re grou ped in to ca tego rie s, whi c h
you can access by clicking the tabs at the top of each page. Each
tab, except fo r th e Ho me t ab which displays when you first log in,
displays the avail able ta sks ho riz ontally t he to p o f the pag e. Y ou
can click on these to display the specific configuration options.
A separate page displays for each task in the task bar. The leftmost task displays by default wh en you cli ck on a new tab. The
same task may appear in more than one ta b, when appro priate. For
example, the Lan Config ta sk displ ays in bot h the LAN tab and the
Routing tab.
Commonly used buttons
The following but ton s a re u sed th rougho ut t he application.
Button Function
Stores in temporary system memory any changes you
have made on the current page. See “Committing your
changes” on page 36 for instructions on storing
changes permanently.
Redisplays the curr ent p age w ith u pda ted
statistics.
When accumulated statistics are displaying, this
button resets the statistics to their initial values.
Launches the online help for the current to pic in a
separate browse r win dow . Hel p i s available from
any main topic page.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
The Home Tab and System View Table
The Home Tab displays the Syste m View table whe n you fir st
access the program:
Figure 8. System View Page
The System View table provide s a snapshot of your system
configuration, and provides links to the software pages that enable
you to configure each setting ( if availabl e). The following table
describes the various sections of the system view table.
Table Heading Description
Device
DSL
WAN Interfaces
Displays basic information about the VisionNet
202ER hardware and software versions, the
system uptime (since the last reboot), and the
preconfigured operating mode.
Displays performance statistics for the DSL line.
You can click the DSL link in the Advanced title
bar to display additional DSL settings, which are
described in Chapter 14.
Displays the software name(s) and various
settings for the device interfaces that
communicate with your ISP via DSL. Although you
only have one physical DSL port, multiple
software-defined interfaces can be configured to
use it. See the ATM VCC, PPP, EOA, and IPoA
chapters (Chapters 12, 13, 14, and 15,
respectively) for more information about the
interfaces defined on you system.
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VisionNet 202ER ADSL Ethernet Router User’s Guid
Table Heading Description
LAN Interfaces
Services Summary
Displays the software names and various settings
for the device interfaces that communicate directly
with your network. These typically include at least
one Ethernet interface, named eth-0, and may
include a USB interface named usb-0. You can
configure some properties of these interfaces, as
described in Chapter 5.
Displays the following service that the VisionNet
202ER performs to help you manage your
network:
o Translating private IP addresses to your
public IP address (NAT, Chapter 8).
o Setting up filtering rules that accept or deny
incoming or outgoing data. (IP Filter,
Chapter 16).
o Enabling router-to-router communication
(RIP, Chapter 9).
o Dynamic assignment or receipt of IP
information (DHCP, Chapter 7).
o Message forwarding based on Internet Group
assignment (IGMP, not configurable).
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VisionNet 202ER ADSL Ethernet Router User’s Guide
Changing the System Date and Time
The device keeps a record of the curren t date and time, whi ch it
uses to calculate and report various performance data.
Changing the Vi sionN et 202E R d at e a nd time doe s no t af fe ct th e
Note
date and time on your PCs.
Follow these inst ru ction s to chang e the da te an d time:
1. At the bottom of the System View page, click
The System – Modify page di splays in a separa te brow ser
window:
Figure 9. System – Modify Page
2. Use the drop-down lists to select a new date and tim e.
3. Click
.
A page displays to confi rm your change.
.
34
4. Click
5. Click
6. Click
to return to the System View page.
Save and Reboot in the Save Setting tab.
to save your changes to permanent memory.
VisionNet 202ER ADSL Ethernet Router User’s Guid
Changing Your Login Password
The first time you log into the Configuration Manager, you use the
default user ID and password (root and root). The system allows
only one user ID a nd pa sswor d. Only the password can be change d.
This user ID and password is only used for logging into the
Configuration Man age r ; i t is not the same as the l ogin you ma y u se
Note
to connect to your ISP (described in Chapter 12).
To change the Configuration Man ager login password:
1. Click the Password Configur ation in the Admin tab
The User Password Con figura tio n p age di splay s by default.
Figure 10. User Password Configuration Page
2. Type your current password in the Old Password text box.
3. Type the new password in the New Password text box and
again in the Confirm New text box.
The password can be up to eigh t ASCII cha racte rs long. When
logging in, you must type the new pa ssword in the same upper
and lower case characters that you use here.
4. Click
5. Click
6. Click
Save and Reboot in the Save Setting tab.
.
to save your changes to permanent memory.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
Committing Your Changes and Rebooting the Device
Committing your changes
Whenever you use the C on figu rat ion Manage r t o change system
settings, the changes are initially placed in temporary storage
(called random access memory or RAM). Your changes are made
effective when y ou s ub mit the m, bu t w ill be lo st i f th e d evi ce i s r e set
or turned off.
To save your changes for future use, you can use the commit
function. This function saves your changes from RAM to permanent
storage (called flash memory).
Submitting change s saves them onl y until the de vice is reset or
Note
powered down. Committing changes saves them permanent ly.
Follow these steps to commi t changes to permanent storage.
1. Click
Save and Reboot in the Save Setting tab.
The Save and Re boo t pag e displays:
Figure 11. Save and Reboot Page
2. Click
. (Disregard the selection in the Reboot Mod e
drop-down list; it does not affect the commit process.)
The changes are saved to permane nt sto rage.
The previous setting s are copied to bac kup storage so that they
can be recalled if your new settings do no t wo r k p rope rly (see
the rebooting in stru ction s on p age 37) .
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VisionNet 202ER ADSL Ethernet Router User’s Guid
Rebootin g the dev ice us ing Conf igu ratio n Man age r
To reboot the device, di splay the Co mmit and Reb oot page , select
the appropriate reboot mode from the drop-down menu, and then
WARNING
click
.
You can select from the following three optio ns when rebo oti ng:
Option Description
Reboot from Last
Configuration
Reboot from Backup
Configuration
Reboot from Default
Configuration
Reboots the device using the current settings in
permanent memory, including any changes you
just committed.
Reboots the device using settings stored in
backup memory. These are the settings that were
in effect before you committed new settings in the
current session.
Reboots the device to default settings provided by
your ISP or the manufacturer. Choosing this
option erases any custom settings.
Do not reboot the device using the Reset button on the back panel
of the VisionNet 202ER to a ctivate new change s. This butt on
resets the device setti ng s to the manuf actur er’ s default val ues.
Any cus tom se tt i ng s wil l be lo s t.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
5 Setting the LAN IP Address
This chapter describes how to configure the interfaces on the
ADSL/Ethernet rout er tha t communi cate with y our LAN..
Configuring your LAN IP address
If you are using the ADSL/Ethernet router with multiple PCs on your
LAN, you must con nect t he LAN via an Ethernet hub t o th e d evi ce 's
LAN port, called eth-0.
You must assign a unique IP addre ss to each device port that you
use.
The instructions tha t foll ow assu me that th e de vice ha s be en
preconfigured to operate in Routing mode, which uses the IP
protocol to de te rmi ne ho w to e xchange d ata am ong yo ur P C s, th e
device, and your ISP. If your device is configured in Bridging
Note
mode, its port s d o n ot req ui re IP a dd resse s. The ope rating mode
displays at the top of the LAN Configu ration pag e and cannot be
changed by the user.
Definition
Note
Configuring the LAN IP Address
The LAN IP add re ss i den ti fies th e L AN po r t (eth -0 ) a s a no de on
your network; that is, its IP address must be in the same subnet as
the PCs on your LA N.
A network node can be thought of as any port on the network,
such as the Vi sionNe t 202ER’s LAN port and the net wo rk int e rfa ce
cards on your PCs. See Ap pe ndi x A fo r an e xpl anatio n o f
subnets..
You can change the default to refle ct the set of IP add re sses that
you want to u se wi th y our netwo r k.
If your networ k u se s a lo cal D HCP serv er (othe r than t he
ADSL/Ethernet router) to assign IP addresses, you can configure
the device to a c cept an d u se a LAN IP address assigned by t hat
server. In this mode, the ADSL/Ethernet router is considered a
DHCP client of your DHCP server.
The VisionNet 202ER itself can function as a DHCP server for
your LAN computers, as described in Chapter 5, but not for its
own LAN port.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
Follow these steps to change the default LAN IP address or to
configure the LAN port as a DHCP client.
1. Launch Configuration Manager, and then click the LAN
Config.
The LAN Configu rat ion pa ge displays, as shown in Figure 12.
Figure 12. LAN Configuration Page
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VisionNet 202ER ADSL Ethernet Router User’s Guid
The LAN Configuration table displays the following settings:
Setting
System Mode
LAN IP
Address
LAN Network
Mask
Use DHCP
Description
The preconfigured mode for your device, such as
Routing or Bridging mode. This setting is not user configurable.
The IP address your computers use to identify the
device’s LAN port.
Note that the public IP address assigned to you by your
ISP is not your LAN IP address. The public IP address
identifies the WAN (ADSL) port on your ADSL/Ethernet
router to the Internet.
The LAN Network mask identifies which parts of the
LAN IP Address refer to your network as a whole and
which parts refer specifically to nodes on the network.
Your device is preconfigured with a default network
mask of 255.0.0.0.
When checked, this setting instructs the device to
accept LAN IP information assigned dynamically from
another DHCP server already configured on your
network. The VisionNet 202ER cannot act as a DHCP
server for its own LAN port.
2. Enter a LAN IP address and network mask, or click the
DHCP Enable radio button.
Entering a fixed address: If you are using routing services
on you LAN su ch a s D HCP a nd NA T, y ou w ill w a nt to
assign a fixed LAN IP address and mask. Th is ensures that
your LAN computers have a fixed address that they use to
communicate with the device.
The IP address you assign must be on the same subnet as
your LAN computers that connect to this port (that is, the
network ID portion o f their IP addr esses and thei r subnet
masks must be the same). See Appendix A for an
explanation of IP addresses and network masks.
You may need to update the DHCP configu rati on so that
the addresses th at t he DHCP se rver dy na mical ly assi gns
to your computers are on the same subnet as the new LAN
IP address. See Ch apt e r 7 fo r in st ruction s on changing the
pool of dynamically assigned addresses. In addi tio n, i f y ou
change the DHCP po ol, y ou w ill al so ne ed to up da te th e
NAT configuration so the new IP add resses are t ranslat ed
properly. See Ch apt e r 8 fo r in st ruction s on N A T.
Enabling DHCP: If another compute r on y our LA N
provides DHCP services for your network, you can click the
DHCP service for the LAN port. Check with your ISP to
determine if this is advisable.
When you clic k th e En abl e radio bu tt on, t he LAN N etw o rk
Mask field will be dimmed (made unavaila ble for ent ry).
The LAN IP Address field will remain edi table, howeve r.
The address that y ou sp eci fy he re w ill be u sed a s a
requested IP address from the DHCP server. This is
41
VisionNet 202ER ADSL Ethernet Router User’s Guide
referred to as a "Configured IP Address" in the program. If
the configured IP add ress is not avai lable fro m the DHCP
server, the serv e r will di str ibu te an oth e r add ress t o the LA N
port. Even if another number is assigned, the same
configured IP address w ill con tinue to di splay in thi s field .
For a description o f how DHC P w or ks, see C hap ter 7.
3. Click
.
If you were using an Ethernet connectio n for the cur rent
session, and changed the IP add re ss, t he conn e ction w ill
be terminated.
I f you enabled the DHCP servi ce , th e ADSL/Ethernet router
will initiate a request for an IP addres s from your LAN' s
DHCP server. A ssumi ng a differ e nt IP a ddre ss i s a s signed ,
your current connection will be terminated .
4. Reconfigure your PCs, if necessary, so that their IP
addresses place them in the same subnet as the new IP
address of the LAN port. See the Quick Start chapter, “Part 2
— Configuring Your Computers,” for instructions.
5. Log into Configuration Manager by typing the new IP
address in your Web browser’s address/location box.
If you enabled DH CP, y ou may ne ed to ch e ck the D HCP se rv er
on your LAN to determine the IP address actually assigned to
the LAN port.
6. If the new settings work properly click
the Save Setting tab.
7. Click
Save and Reboot in
to save your changes to permanent memory.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
6 Viewing System IP Information and
Performance S tatistics
The interfaces on the VisionNet 202ER that communicate with other
network and Internet devices are identified by unique Internet
protocol (IP) addresses. You can use the Configuration Manager to
view the list of IP addresses that your device uses, and to view
other system and network performance data.
See Appendix A fo r a de scriptio n o f IP addr e sses an d masks.
Viewing the VisionNet 202ER’s IP addresses
To view the VisionNet 202ER’s IP addresse s, click IP A dd ress in
the System Status tab. The IP Address Table page displays, as
shown in Figur e 13 :
Figure 13. IP Address Table Page
The table lists the IP addresses, network masks (“Net Mask”), and
interface names (“IF Name”) for each of its IP-enabled interfaces.
The listed IP addresses may include:
The IP address of the device’s LAN (Ethernet) port, called
eth-0. See Chapter 5 for instructions on configuring this
address.
The IP address of the WAN (ADSL line) interface, which
your ISP and othe r ext e rnal d evi ces u se t o i den ti fy y our
network. It may be identified in the Configuration Manager
by the names ppp -0 or eoa-0 , o r ipoa-0, dep endi ng on t he
protocol y our device uses to communicate with your ISP.
Your ISP may assign the same address each time, or it
may change ea ch ti me y ou re conn ect .
The “loopback” IP address, named lo-0, of 127.0.0.1 . This
is a special add ress t ha t enabl e s the d evi ce to ke ep any
data addressed directly to it, rather than route the data
through the WAN or LAN ports.
If your device ha s additional IP-enabled inte r fa ces, th e IP
addresses of these will also display.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
Viewing IP Global Statistics
You can view st ati sti cs on the pro ce ssing o f In te rnet p roto col
packets (a packet i s a co llectio n o f da ta th at has b een bun dled fo r
transmission). You wi ll no t typi cally ne ed to view thi s da ta, but y ou
may find it help ful w hen w orking w it h y ou r ISP to di agn o se ne tw o rk
and Internet da ta t ran smission p r oble ms.
To view global IP statistics, click
on the IP
Address Table page. Figure 14 shows the IP Glo bal Statist ics
page:
44
Figure 14. IP Global Statistics Page
To display update d sta ti stics sh ow ing any new data since you
opened the page, click
.
VisionNet 202ER ADSL Ethernet Router User’s Guide
7 Configuring Dy namic Host Configuration
Protocol
You can configure your netwo rk and Vision Net 202E R to use the
Dynamic Host Configuration Protocol (DHCP). This chapter
provides an overview of DHCP and instructions for implementing it
on your network.
Overview of DHCP
What is DHCP?
DHCP is a pro tocol t ha t e nabl e s netw o rk ad mi ni st rato rs to cent ral ly
manage the assignment and di stribu tion of IP in for mation to
computers on a network.
When you enable DHCP on a network, you allow a device — such
as the VisionNe t 202E R o r a rou te r l o cated w ith your ISP — to
assign temporary I P a dd resses t o y ou r co mputer s wheneve r they
connect to your network. The assigning devi ce is called a DHCP
server, and the receivi ng device is a DHCP clien t.
Note
If you used the Quick Start instructions, you either configured
each LAN PC with a n IP a ddre ss, or you spe cified that i t w ill
receive IP information dynamically (automatically). If you chose to
have the information assigned dynamically, then you configured
your PCs as DHCP clients that will accept IP addresses assigned
from a DCHP server such as the Vision Net 202E R.
The DHCP server draws from a de fined pool of IP addresse s and
“leases” them for a specified amount of time to your computers
when they request an Internet session. It monitors, collects, and
redistributes the a dd res ses as nee ded.
On a DHCP-enabled netw ork, the IP info rmati on is assi gned
dynamically rather than statically. A DHCP client can be assigned a
different addre ss from the pool each ti me it re connect s to the
network.
Why use DHCP?
DHCP allows you to manage and di stribute IP add re sses
throughout your netw or k from a central compute r. Without DHCP,
you would have to configure each compute r separa tely with IP
addresses and related information. DHCP is commonly used with
large networks and thos e that are freq uently expande d or othe rwise
updated.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
VisionNet 202ER DHCP modes
The device can be configured as a DHCP server, DHCP relay
agent, or, i n some c a ses , a D HC P cli ent .
If you configure the device as a DHCP server, it will
I f your ISP perfor ms the DCHP serv er func tion fo r your
If you have another PC or device on your network that is
maintain the pool of addre sses and di stribute the m to your
LAN computers. If the pool of addresses includes private IP
addresses, you must also configure the Network Address
Translation service, so that the private addresses can be
translated to your public IP ad dress on the Inte rnet. Both
DHCP server and NAT are enable d in the de fault
configuration.
network, then you can co nfigu re the device as a DHCP
relay agent. When the VisionNet 202ER receives a request
for Internet access from a computer on your network, it
contacts y our ISP for the necessary IP information, and
then relays the assigne d informatio n back to the computer .
already performi ng the DH CP serve r fun ction, then you can
configure the LAN po r t on the Vi si onN et 20 2ER t o b e a
DHCP client of that server (as are your PCs). This
configuration is not discussed in this chapter. See Chapter
5 for instructions.
Note
You can input settings for both DH CP serve r and DHCP rel ay
mode, and then a cti vate eit he r mo de at an y t ime . De -activa ted
settings are retain ed for your future use.
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VisionNet 202ER ADSL Ethernet Router User’s Guid
Configuring DHCP Server
By default, the de vice is configured as a DH CP ser ver, wi t h a
Note
predefined IP add r e ss pool of 1 0.0 .0 .4 th r ough 1 0. 0.0 .1 5 ( su bne t
mask 255.255.255.0 ). To cha nge this range of addresses, see
“Viewing, modifying , a nd dele ting a dd ress po ols” on page 50.
First, you must configure y our PCs to accept DHCP information
assigned by a D HCP serve r :
1. Open the Windows Control Panel and display the computer's
Networking properties. Configure the TCP/IP properties to
"Obtain an IP address automatically" (the actual text may
vary depending on your operating system). For detailed
instructions, see the Quick Start chapter, “Part 2 —
Configuring Your Computer s. ”
Next, you define t he po ol s of IP ad dr e sses y ou w ant t o make
available for distribution to your computers. These addresses can
be multiple public addre sses that you hav e purchased from your
ISP, but are typically private addresses that you create. (LAN
administrators often create private IP addresses for use only on
their networ ks. See “ Overview o f NA T” o n page 5 5. )
2. Launch Configuration Manager, click
DHCP Server in the
LAN tab.
The DHCP Server Con figu rat ion pa ge di splays:
Figure 15. DHCP Configuration Page
Each pool you create displays in a row on the tab le on this
page.
You can create up to eight pool s; however, most user s will
need to create only one fo r thei r LAN.
3. To add an IP address pool, click
.
The DHCP Server Pool – A dd pa ge di sp lay s.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
Figure 16. DHCP Server Pool – Add Page
48
VisionNet 202ER ADSL Ethernet Router User’s Guid
4. The Start IP Address, End IP Address, Net Mask, and
Gateway Address fields are required; the others are optional.
Field Description
Start/End IP
Addresses
Mac
Address
Net Mask
Domain
Name
Specify the lowest an d high est a dd resse s in
the pool.
Use this field on ly if you want to assign a
specific IP address to a specific computer (that
is, you are cr eating an e xce pt ion t o the
dynamic assignment of addresse s). The IP
address you specify w ill b e assig ned t o the
computer that corresponds to this MAC
address. (A MAC address is a manufacturerassigned hardware ID that is unique for ea ch
device on a ne twor k.) If you type a MAC
address here, you must have speci fied the
same IP address in both the Start IP Address
and End IP Addre s s fiel d s.
Specifies which portion of each IP address in
this range refers to the netwo rk and whi ch
portion refers to the host (computer). For a
description of network masks and LA N
network masks, see Appendix A. You can use
the network mask to distinguish which pool of
addresses should be distributed to a particular
subset of computers on your LAN (called a
subnet).
A user-friendly name that refers to the group of
computers (subnet) th at w ill b e a ssign ed
addresses from this pool.
Gateway
Address
The address of the default gateway for
computers that receive IP addresses from this
pool. The default gateway is the IP address
that the computers first contact to
communicate with the Internet. Typically, it is
the device’s LAN port IP address. See “Hop s
and gateways” o n pag e 7 8 fo r an e xplan ati on
of gateway addresses.
DNS The IP address of the Domain Name Se r ver to
be used by computers that receive IP
addresses from this pool. The DNS translates
common Internet names that you type into
your web browser into their equivalent numeric
IP addresses. Typi cally , thi s se rv er i s lo cate d
with your ISP.
SDSN...SWI
NS
(optional)
The IP addresses of devices that perform
various services for computers th at receive IP
addresses from this pool. Typically, these
devices are servers located with your ISP. See
the glossary for a definition of each type of
server.
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VisionNet 202ER ADSL Ethernet Router User’s Guide
5. Click .
A confirmation p age di splay s b riefly to in di cat e that th e p ool h a s
been added successfully. After a few se cond s, t he DH CP
Server Pool – Add pag e di splay s w ith t he newly added pool.
6. Follow the instructions in “Setting the DHCP Mode” on
page 53 to set the DHCP mode to DHCP Server.
Viewing, modif ying, and deleting address pools, and
excluding IP addresses from a pool
To view, modify, or delete an exi sting add ress pool, display the
DHCP Server Configurati on page , and cli ck the icon s in the
corresponding row in the address pool table.
To del ete an IP add ress pool, cli ck
, then submit a nd
commit your changes.
To view d et ail s on an IP ad dre ss po ol, cli ck
. A page
displays with all t he same in fo rmati on y ou en te red w he n
adding the pool.
To mod i fy th e do main na me a ss o ciated w i th an IP a dd ress
pool, or to exclude addresses from the pool, click
. The
DHCP Server Pool – Modi fy page di splay s .
The DHCP Server Po ol – Modify page is shown in Fi g ur e
17.
50
Figure 17. DHCP Server Pool – Modify Page
Excluded addresse s a re those t hat you have designated
for fixed use with specific devices, or for some other reason
do not want to make avai lable t o y ou r netwo r k.
To exclude an address from distribution, type it in the fields
provided and click
. Click after entering you r
changes. Be sure to use the Co mmit featu re to save y our
changes to permanent memory, a s described on pag e 36.
Viewing current DHCP address assignments
When the VisionNet 202ER fun ction s as a DHCP serve r for your
LAN, it keeps a re co rd o f a ny addresses it has leased to y ou r
VisionNet 202ER ADSL Ethernet Router User’s Guid
computers. To view a table of all current IP address assignments,
display the DHCP Server Config uration page, and th en
click
.
A page display s si mila r to t he on show n in Fi g ur e 18 :
Figure 18. DHCP Server Address Table Page
The DHCP Server Address Table lists any IP addresses that are
currently leased t o LAN device s . For ea ch l ea sed add ress, the table
lists the following information:
Field Description
IP Address
Netmask
Mac Address
The address that has been leased from the pool.
The network mask associated with the leased address,
which identifies the network ID and host ID portions of
the address (see Appendix A).
A hardware ID for the devi ce to whi ch the nu mber
has been assigne d.
Pool Start
The lower bounda ry o f the ad d res s pool
(provided to identi fy the pool fro m which the
leased number came).
Address Type Static or Dyna mic. Static indicates that t he IP
number has been assigned permanently to the
specific hardware device. Dynamic indicat es tha t
the number has be en lea sed te mpora rily for a
specified length of time.
Time
Remaining
The amount of time left for the device to use the
assigned address.
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