Specifications

Serial Interface Configuration Examples
IC-120
Cisco IOS Interface Configuration Guide
PA-T3 and PA-2T3 Configuration Example
The following example shows a typical configuration for serial interface 1/0/0 on a PA-T3 serial port
adapter in a Cisco 7500 series router. The dsu bandwidth command reduces the bandwidth by
padding the T3 frame, and the dsu mode command enables and improves interoperability with other
DSUs.
Router# configure terminal
Router(config)# interface serial 1/0/0
Router(config-if)# ip address 1.1.1.10 255.255.255.0
Router(config-if)# clock source internal
Router(config-if)# crc 32
Router(config-if)# dsu bandwidth 16000
Router(config-if)# dsu mode 0
Router(config-if)# no scramble
Router(config-if)# framing c-bit
Router(config-if)# no shutdown
Router(config-if)# ^Z
Packet OC-3 Interface Configuration Examples
The examples in this section include a simple configuration and a configuration for two routers back
to back.
Packet OC-3 Configuration with Default Values Accepted
In the following example, the default framing, MTU, and clock source are accepted, and the interface
is configured for the IP protocol:
interface pos 3/0
ip address 172.18.2.3 255.0.0.0
Two Routers Connected Back to Back
To connect two routers, attach the cable between the Packet OC-3 port on each. By default, the POS
uses loop timing mode. For back-to-back operation, only one of the POSs may be configured to
supply its internal clock to the line.
In the following example, two routers are connected back to back through their Packet OC-3
interfaces:
First router
interface pos 3/0
ip address 170.1.2.3 255.0.0.0
no keepalive
pos internal-clock
Second router
interface pos 3/0
ip address 170.1.2.4 255.0.0.0
no keepalive
The following example shuts down the entire T1 line physically connected to a Cisco 7500 series
routers
:
controller t1 4/0
shutdown