WAN INTERFACE CONFIGURATION
PPP
• Point to Point Protocol
• Open Standard Protocol (works with same and different company Routers i.e. Cisco–Nortel, Cisco–Multicom.
• Supports Authentication
• Supports Compression
HDLC
• High level Data link Control
• Vendor proprietary Protocol (works with same company Router only, i.e. Cisco-Cisco, Nortel-Nortel, etc.)
• No Support for Authentication
• No Support for Compression
Device Classification
DCE
• Data Communication Equipment
• Generate clocking
(i.e. Speed).
• Master
• Example of DCE device in Leased line setup : V.35 & G.703 Modem & Exchange (Modem & MUX)
• Example of DCE device in Dial up setup : Dialup Modem
DTE
• Data Termination Equipment
• Accept clocking
(i.e. Speed).
• Slave
• Example of DTE device in Leased line setup : Router
• Example of DTE device in Dial up setup : Computer
1.Configuring a serial interface
• A Back to Back Cable is used which emulates the copper wire, modems and MUX , the complete exchange setup.
• Without DCE & DTE device communication is not possible.
The first step to establish the WAN connection is to configure the Serial (WAN) interface.
By default the serial interface on the Router does not have IP address, encapsulation is HDLC and the interface is in shutdown state.
To check for DTE or DCE interface, so that the clock rate can be configured on the DCE interface.
Syntax:
Output:
Interface Serial0/0
Hardware is PowerQUICC MPC860
DTE V.35 TX and RX clocks detected
idb at 0x8096C8CC, driver data structure at 0x80971DD0
SCC Registers:
General [GSMR]=0x2:0x00000030, Protocol-specific [PSMR]=0x8
Events [SCCE]=0x0000, Mask [SCCM]=0x001F, Status [SCCS]=0x06
Transmit on Demand [TODR]=0x0, Data Sync [DSR]=0x7E7E
---More ---
The following are the commands to assign IP, encapsulation & enable the serial port:
Syntax:
Router(config-if)#ip address <ip> <mask>
Router(config-if)#encapsulation <ppp> or <hdlc>
Router(config-if)#clockrate <bandwidth>
Router(config-if)#no shutdown
example:
WAN Interface Configuration
ON CHE:
CHE#configure terminal
CHE(config)#interface serial 0
CHE(config-if)#ip address 172.16.0.1 255.255.0.0
CHE(config-if)#no shutdown
CHE(config-if)#encapsulation hdlc
CHE(config-if)#^z
ON HYD:
HYD (config) #interface serial 1
HYD(config-if)#ip address 172.16.0.2 255.255.0.0
HYD(config-if)#no shutdown
HYD(config-if)#clock rate 64000
HYD(config-if)#encapsulation hdlc
HYD(config) #interface serial 0
HYD(config-if)#ip address 172.17.0.1 255.255.0.0
HYD(config-if)#no shutdown
HYD(config-if)#encapsulation hdlc
HYD(config-if)#clock rate 64000
HYD(config-if)#^z
ON BAN:
BAN(config)#interface serial 1
BAN(config-if)#ip address 172.17.0.2 255.255.0.0
BAN(config-if)#no shutdown
BAN(config-if)#encapsulation
to verify
To verify, the following commands can be give on
all Routers
Router#show interface serial <number>
Syntax:
Router#show interface serial <no>
HYD#show interface serial 0/0
Serial0/0 is up, line protocol is up
Hardware
is PowerQUICC Serial
Internet address is 172.17.0.1/16
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 00:00:02, output 00:00:01, output
hang never
Last clearing of "show interface"
counters never
Input queue: 0/75/0 (size/max/drops);
Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max
total/threshold/drops)
Conversations 0/2/256 (active/max active/max
total)
Reserved Conversations 0/0 (allocated/max
allocated)
5
minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0
packets/sec
1047 packets input, 68589 bytes, 0 no
buffer
Received 584 broadcasts, 0 runts, 0 giants, 0
throttles
0 input errors, 0 CRC, 0 frame, 0
overrun, 0 ignored, 0 abort
1021 packets output, 69756 bytes, 0
underruns
0 output errors, 0 collisions, 13
interface resets
0
output buffer failures, 0 output buffers swapped out
28 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
