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ATM Switch Router Software Configuration Guide
OL-7396-01
Chapter18 Configuring Interfaces
Configuring OC-3c MMF Interfaces (Catalyst8540 MSR)
Example
The following example configures ATM interface 3/1/1 as the network side of a private UNI running
version 3.1.
Switch# interface atm 3/1/1
Switch(config-if)# no atm auto-configuration
Switch(config-if)#
%ATM-6ILMIOAUTOCFG: ILMI(ATM/0/0): Auto-configuration is disabled, current interface
parameters will be used at next interface restart.
Switch(config-if)# atm uni version 3.1
See Troubleshooting the Interface Configuration, page 18-17 to confirm your interface configuration.
Configuring OC-3c MMF Interfaces (Catalyst 8540 MSR)
The 16-port OC-3c MMF interface module provides short-reach interc ampus and WAN ATM
connections. The OC-3c interface module provides an interface to ATM switching fabrics for
transmitting and receiving data bidirectionally at up to 155 Mbps. The OC-3c interface module can
support interfaces that connect to the OC-3c MMF STS-3c/STM1 physical layer.
The Catalyst 8540 MSR supports up to eight OC-3c interface modules per chassis, with a ma ximum of
128 OC-3c interface ports.
Note You can configure traffic pacing on the interfaces to allow the aggregate output traffic rate on any
interface to be set to a rate below the line rate. This feature is useful when communicating with a slow
receiver or when connected to public networks with peak-rate tariffs.

Default OC-3c MMF Interface Configuration without Autoconfiguration

(Catalyst 8540 MSR)
If Integrated Local Management Interface (ILMI) has been disabled or if the connecting end node does
not support ILMI, the following defaults are assigned to all OC-3c interfaces:
ATM interface type = UNI
UNI version = 3.0
Maximum virtual path identifier (VPI) bits = 8
Maximum virtual channel identifier (VCI) bits = 14
ATM interface side = network
ATM UNI type = private
Framing = sts-3c
Clock source = network-derived
Step6 Switch(config-if)# clock source {free-running |
loop-timed | network-derived}
Modifies the clock source.
Step7 Switch(config-if)# scrambling {cell-payload |
sts-stream}
Modifies the scrambling mode.
Command Purpose