HDLC Protocol Configuration

HDLC is the default protocol used by CISCO routers. A new router uses HDLC Encapsulation by default when no encapsulation protocol is specified.
1. Related commands
Port Settings
　
Note: 1. The following example shows the Cisco synchronous serial port status.
Router # show interface serial 0
Serial 0 is up, line protocol is up
Hardware is MCI Serial
Internet address is 150.136.190.203, subnet mask is 255.255.255.0
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation HDLC, loopback not set, keepalive set (10 sec)
Last input 0:00:07, output 0:00:00, output hang never
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
Five minute input rate 0 bits/sec, 0 packets/sec
Five minute output rate 0 bits/sec, 0 packets/sec
16263 packets input, 1347238 bytes, 0 no buffer
Received 13983 broadcasts, 0 runts, 0 giants
2 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 2 abort
22146 packets output, 2383680 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets, 0 restarts
1 carrier transitions
2. Example
　
The settings are as follows:
Router1:
Interface Serial0
Ip address 192.200.10.1 255.255.255.0
Clockrate 1000000
Router2:
Interface Serial0
Ip address 192.200.10.2 255.255.255.0
!
3. Use the E1 line as an example to connect multiple 64 k leased lines.
Related commands:

Note: 1. when the link is T1, the channel-group number is 0-23, and the Timeslot range is 1-24. When the link is E1, the channel-group number is 0-30, timeslot range: 1-31.
2. Use show controllers e1 to observe the controller status. The following figure shows the normal status of controllers when the frame type is crc4.
Router # show controllers e1
E1 0/0 is up.
Applique type is Channelized E1-unbalanced
Framing is CRC4, Line Code is HDB3 No alarms detected.
Data in current interval (725 seconds elapsed ):
0 Line Code Violations, 0 Path Code Violations
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
Total Data (last 24 hours) 0 Line Code Violations, 0 Path Code Violations,
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins,
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
The following example shows how to connect three 64 k leased lines with a frame type of NO-CRC4 and a non-balanced link. The router configuration is as follows:
Shanxi # wri t
Building configuration...
Current configuration:
!
Version 11.2:
No service udp-small-servers
No service tcp-small-servers
!
Hostname shanxi
!
Enable secret 5 $1 $ XN08 $ Ttr8nfLoP9.2RgZhcBzkk/
Enable password shanxi
!
!
Ip subnet-zero
!
Controller E1 0
Framing NO-CRC4
Channel-group 0 timeslots 1
Channel-group 1 timeslots 2
Channel-group 2 timeslots 3
!
Interface Ethernet0
Ip address 133.118.40.1 255.255.0.0
Media-type 10 BaseT
!
Interface Ethernet1
No ip address
Shutdown
!
Interface Serial0: 0
Ip address 202.119.96.1 255.255.255.252
No ip mroute-cache
!
Interface Serial0: 1
Ip address 202.119.96.5 255.255.255.252
No ip mroute-cache
!
Interface Serial0: 2
Ip address 202.119.96.9 255.255.255.252
No ip mroute-cache
!
No ip classless
Ip route 133.210.40.0 255.255.255.0 Serial0: 0
Ip route 133.210.41.0 255.255.255.0 Serial0: 1
Ip route 133.210.42.0 route 255.255.0 Serial0: 2
!
Line con 0
Line aux 0
Line vty 0 4
Password shanxi
Login
!
End