CISCO路由器配置手冊－第二章（廣域網協議設置HDLC）
一、HDLC
　
HDLC是CISCO路由器使用的缺省協議，一臺新路由器在未指定封裝協議時默認使用HDLC封裝。
1. 有關命令
端口設置
任務
命令
設置HDLC封裝
encapsulation hdlc
設置DCE端線路速度
clockrate speed
復位一個硬件接口
clear interface serial unit
顯示接口狀態
show interfaces serial [unit] 1
注:1.以下給出一個顯示Cisco同步串口狀態的例子.
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. 舉例

設置如下：
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. 舉例使用E1線路實現多個64K專線連接.
相關命令:
任務
命令
進入controller配置模式
controller {t1 | e1} number
選擇幀類型
framing {crc4 | no-crc4}
選擇line-code類型
linecode {ami | b8zs | hdb3}
建立邏輯通道組與時隙的映射
channel-group number timeslots range1
顯示controllers接口狀態
show controllers e1 [slot/port]2