4-18
Layer 3 Switching Software Feature and Configuration Guide
78-6235-04, Cisco IOS Release 12.0(10)W5(18)
Chapter4 Configuring Interfaces
Configuring the POS OC-12c Uplink Interface (Catalyst8540)
Configuring Framing
The default framing mode for the POS OC-12c uplink interface is SONET STS-12c. You can also
configurethe interface for SDH STM-4, which is more widely used in Europe. To configure the framing
mode on the POS OC-12c uplink interface, perform the following steps, beginning in global
configuration mode:
Configuring SONET Overhead
Youcan set the SONET overhead bytes in the frame header to meet a specific standards requirement or
to ensure interoperability of the POS OC-12c uplink interface with another vendor's equipment. To
configure the SONET overhead, perform the following steps, beginning in global configuration mode:
Command Purpose
Step1 Router(config)# interface pos
slot/subslot/interface
Router(config-if)#
Enters interface configuration mode and specifies the POS
interface to configure.
Step2 Router(config-if)# pos framing
{sdh | sonet}Configures the framing mode.
POS framing defaults to SONET. The following default values
are used for SONET.
•s1s0 default value is 0.
•J1 defaults set to host name, interface name, and IP address.
The following default values are used for SDH framing:
•s1s0 default value is 2.
•J1 is the path trace string. Its default setting is empty and is
not configurable.
Step3 Router(config-if)# no shutdown Enables the interface with the previous configuration.
Command Purpose
Step1 Router(config)# interface pos
slot/subslot/interface
Router(config-if)#
Enters interface configuration mode and specifies the POS
interface to configure.
Step2 Router(config-if)# pos flag {c2
value | j0 value | sls0 value}Configures the SONET overhead bytes.c2 is a path signal
identifier,j0 is the section trace byte, and sls0 is the bit s1 and s0
of the H1 payload pointer byte.
Step3 Router(config-if)# no shutdown Enables the interface with the previous configuration.