Cisco 15327 - Manual (Page 89)

5-9
Ethernet Card Software Feature and Configuration Guide, R7.2
Chapter 5 Configuring POS
Monitoring and Verifying POS
Third-Party POS Interfaces C2 Byte and Scrambling Values
If a Cisco POS interface fails to come up when connected to a third-party device, confirm the scrambling
and cyclic redundancy check (CRC) settings as well as the advertised value in the C2 byte. On routers
from Juniper Networks, configuring RFC 2615 mode sets the following three parameters:
• Scrambling enabled
• C2 value of 0x16
• CRC-32
Previously, when scrambling was enabled, these third-party devices continued to use a C2 value of 0xCF,
which did not properly reflect the scrambled payload.
Configuring SPE Scrambling
SPE scrambling is on by default. To configure POS SONET/SDH Payload (SPE) scrambling, perform
the following steps, beginning in global configuration mode:
Monitoring and Verifying POS
The show controller pos [0 | 1] command ( Example 5-1 ) outputs the receive and transmit values and the
C2 value. Thus, changing the value on the local end does not change the value in the show controller
command output.
Example 5-1 show controller pos [0 | 1] Command
ML_Series# sh controllers pos 0
Interface POS0
Hardware is Packet/Ethernet over Sonet
Framing Mode: HDLC
0x16 Cisco HDLC or PPP/BCP with scrambling
0x1B GFP-F
Table 5-5 C2 Byte and Scrambling Default Values (continued)
Signal Label SONET/SDH Payload Contents
Command Purpose
Step 1 Router(config)# interface pos
number
Enters interface configuration mode and specifies the POS
interface to configure.
Step 2 Router(config-if)# no pos
scramble-spe
Disables payload scrambling on the interface. Payload
scrambling is on by default.
Step 3 Router(config-if)# no shutdown Enables the interface with the previous configuration.
Step 4 Router(config-if)# end Returns to the privileged EXEC mode.
Step 5 Router# copy running-config
startup-config
(Optional) Saves configuration changes to NVRAM.