Network Router User Manual

Nortel Secure Router 8000 Series
Configuration -WAN Access 7 LAPB and X.25 configuration
Issue 5.3 (
30 March 2009) Nortel Networks Inc. 7-51
[RouterA-Serial1/0/0] link-protocol x25
[RouterA-Serial1/0/0] x25 x121-address 21
[RouterA-Serial1/0/0] x25 vc-range bi-channel 9 1024
[RouterA-Serial1/0/0] x25 pvc 3 ip 192.149.13.2 x121-address 22 broadcast packet-size
512 512 window-size 5 5
[RouterA-Serial1/0/0] shutdown
[RouterA-Serial1/0/0] undo shutdown
[RouterA-Serial1/0/0] quit
Step 2 Configure Router B.
<RouterB> system-view
[RouterB]
interface ethernet 2/0/0
[RouterB-Ethernet2/0/0] ip address 196.25.231.1 255.255.255.0
[RouterB-Ethernet2/0/0] quit
[RouterB] interface serial 1/0/0
[RouterB-Serial1/0/0] ip address 192.149.13.2 255.255.255.0
[RouterB-Serial1/0/0] link-protocol x25
[RouterB-Serial1/0/0] x25 x121-address 22
[RouterB-Serial1/0/0] x25 vc-range bi-channel 9 1024
[RouterB-Serial1/0/0] x25 pvc 4 ip 192.149.13.1 x121-address 21 broadcast packet-size
512 512 window-size 5 5
[RouterB-Serial1/0/0] shutdown
[RouterB-Serial1/0/0] undo shutdown
In the preceding configuration, the PVC numbers of Router A and Router B are different,
being 3 and 4 respectively.
The following concepts compare "VC" and "LC".
z
VC refers to the end-to-end logic link between the calling DTE and the called DTE.
z
LC refers to the logic link between two directly connected devices (either between DTE
and DCE, or between the ports of two packet switching exchanges).
A VC consists of several LCs and each LC has a separate number. The VC between Router A
and Router B is shown in
Figure 7-15. (Assume that this VC passes four packet switches in
the network.)
Figure 7-15 One VC consisting of several LCs
RouterA
LC3
LC243
LC3
LC24
LC4
PBX
PBX
PBX
PBX
RouterB
PVC 3 and PVC 4 refer to the numbers of the LCs between the router and the switch directly
connecting to it. On one side of this VC, you can use the LC number to identify the VC with
no strict distinction between the VC and logical channel.