Nortel Networks 8000 - Manual (Page 72)

Nortel Secure Router 8000 Series
Configuration -WAN Access 4 POS and CPOS interface configuration
When choosing the clock mode for the POS interface, note the following:
• When the POS interfaces of two routers are connected directly or through the
Wavelength Division Multiplexing (WDM), you configure one end to use master clock
mode and the other end to use slave clock mode.
• When the POS interface of the router is connected with switching devices, you set the
POS interface as the slave clock mode.
By default, the clock mode is the master clock mode.
—End
4.2.4 Configuring overhead bytes
Do as follows on the routers:
Step 1 Run:
system-view
The system view appears.
Step 2 Run:
interface pos interface-number
The POS interface view appears.
Step 3 Run:
flag { c2 | j0 | j1 } h ex-value
The command configures the overhead bytes of the POS interface are configured.
The SONET/SDH provides a variety of overhead bytes, which perform the monitoring
function of different levels.
The C2 (Path signal label byte) is included in higher order path overhead. C2 indicates the
multiplex structure of VC frame and the property of information payload.
The J0 (Regeneration section Trace Message) is included in section overhead. You use it to
test the continuous connection of the two ports on the section level.
You use the J1 (Higher-Order VC-N path trace byte) to test the connectivity of two interfaces.
Configure C2, J0 and J1 to be consistent. Otherwise an alarm generates.
For the POS interface, the default value of C2 is 16 (hexadecimal), the default value of J0 is 0
(hexadecimal) and the default value of J1 is 0 (hexadecimal).
—End
4.2.5 Configuring frame format
Do as follows on the routers:
Step 1 Run:
system-view
Issue 5.3 (30 March 2009) Nortel Networks Inc. 4-11