Configuring ISDN 128K leased lines
Network requirements
As shown in Figure 21, Router A and Router B are connected by connecting their ISDN BRI interfaces through a 128K leased line.
Figure 21: Network diagram
![](images/image19.png)
Configuration procedure
Configure Router A:
<RouterA> system-view [RouterA] dialer-rule 1 ip permit [RouterA] interface bri 2/0 [RouterA-Bri2/0] ip address 100.1.1.1 255.255.255.0 [RouterA-Bri2/0] link-protocol ppp [RouterA-Bri2/0] dialer enable-circular [RouterA-Bri2/0] dialer-group 1 [RouterA-Bri2/0] dialer isdn-leased 128k
Configure Router B:
<RouterB> system-view [RouterB] dialer-rule 1 ip permit [RouterB] interface bri 2/0 [RouterB-Bri2/0] ip address 100.1.1.2 255.255.255.0 [RouterA-Bri2/0] link-protocol ppp [RouterB-Bri2/0] dialer enable-circular [RouterB-Bri2/0] dialer-group 1 [RouterB-Bri2/0] dialer isdn-leased 128k
After you configure a leased line successfully, you can dial through. To view the interface states, execute the following commands:
<RouterA> display interface bri 2/0 Bri2/0 current state :UP Line protocol current state :UP (spoofing) Description : Bri2/0 Interface The Maximum Transmit Unit is 1500, Hold timer is 10(sec) baudrate is 128000 bit/s, Timeslot(s) Used: 1, 2 Internet Address is 100.1.1.1/24 Encapsulation is ISDN Output queue : (Urgent queue : Size/Length/Discards) 0/50/0 Output queue : (Protocol queue : Size/Length/Discards) 0/500/0 Output queue : (FIFO queuing : Size/Length/Discards) 0/75/0 Last 300 seconds input rate 0.00 bytes/sec, 0.00 packets/sec Last 300 seconds output rate 0.00 bytes/sec, 0.00 packets/sec Input: 0 packets, 0 bytes 0 broadcasts, 0 multicasts 2 errors, 0 runts, 0 giants, 2 CRC, 0 align errors, 0 overruns, 0 dribbles, 0 aborts, 0 no buffers 0 frame errors Output:0 packets, 0 bytes 0 errors, 0 underruns, 0 collisions 0 deferred <RouterA> display interface bri 2/0:1 Bri2/0:1 current state :UP Line protocol current state :UP (spoofing) Description : Bri2/0:1 Interface The Maximum Transmit Unit is 1500 baudrate is 128000 bit/s, Timeslot(s) Used: 1, 2 Link layer protocol is PPP LCP opened, IPCP opened, OSICP opened Output queue : (Urgent queue : Size/Length/Discards) 0/50/0 Output queue : (Protocol queue : Size/Length/Discards) 0/500/0 Output queue : (FIFO queuing : Size/Length/Discards) 0/75/0 Last 300 seconds input rate 2.44 bytes/sec, 0.20 packets/sec Last 300 seconds output rate 2.54 bytes/sec, 0.20 packets/sec Input: 17782 packets, 220973 bytes 0 broadcasts, 0 multicasts 2 errors, 0 runts, 0 giants, 2 CRC, 0 align errors, 0 overruns, 0 dribbles, 0 aborts, 0 no buffers 0 frame errors Output:17085 packets, 208615 bytes 0 errors, 0 underruns, 0 collisions 0 deferred <RouterA> display interface bri 2/0:2 Bri2/0:2 current state :DOWN Line protocol current state :UP (spoofing) Description : Bri2/0:2 Interface The Maximum Transmit Unit is 1500 baudrate is 64000 bit/s, Timeslot(s) Used: NULL Link layer protocol is PPP LCP initial Output queue : (Urgent queue : Size/Length/Discards) 0/50/0 Output queue : (Protocol queue : Size/Length/Discards) 0/500/0 Output queue : (FIFO queuing : Size/Length/Discards) 0/75/0 Last 300 seconds input rate 0.16 bytes/sec, 0.01 packets/sec Last 300 seconds output rate 0.16 bytes/sec, 0.01 packets/sec Input: 17494 packets, 216768 bytes 0 broadcasts, 0 multicasts 2 errors, 0 runts, 0 giants, 2 CRC, 0 align errors, 0 overruns, 0 dribbles, 0 aborts, 0 no buffers 0 frame errors Output:16634 packets, 201465 bytes 0 errors, 0 underruns, 0 collisions 0 deferred
As you can see, the state of interface Bri 2/0:1 is up, its speed is 128 kbps, and channels (timeslots used) B1 and B2 are in use; the state of Bri 2/0:2 is down, and the field of timeslots used is NULL.
![]() | NOTE: You do not need to configure a dial number because setup of leased line connection does not involve dialing process. | |