Configuring ISDN 128K leased lines

As shown in Figure 21, Router A and Router B are connected by connecting their ISDN BRI interfaces through a 128K leased line.

1. 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
   

2. 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.