Configuring CDR

Clock and Data Recovery (CDR) is a process that is dependent upon a clock signal synchronous with the data flow. When a data flow arrives at the receiver, it is sent without additional clocking information, the receiver generates a clock from an approximate frequency reference, and then phase-aligns the clock to the transitions in the data flow with a phase-locked loop (PLL). Data distortion, noise, and jitter on the incoming data can be reduced if the CDR technology is used for data recovery from the transmission channel.

NOTE:

- CDR function can only be configured on the 100G or 40G optical module interface and the four interfaces it breaked out from.
- The CDR configurations of the four interfaces which breaked out from the 100G or 40G optical module interface should be the same.

Procedure

- Use the following command to disable or enable the CDR function.

ovs-vsctl set interface <interface-name> options:cdr-admin-state=[true | false]

The default setting is true. The command takes effect immediately after committing.

- Use the following command to remove CDR function.

ovs-vsctl remove interface <interface-name> options cdr-admin-state

Configuration Example

Enable the CDR function on interface te-1/1/1~te-1/1/4.

admin@PICOS-OVS$ovs-vsctl set interface te-1/1/1 options:cdr-admin-state=true
admin@PICOS-OVS$ovs-vsctl set interface te-1/1/2 options:cdr-admin-state=true
admin@PICOS-OVS$ovs-vsctl set interface te-1/1/3 options:cdr-admin-state=true
admin@PICOS-OVS$ovs-vsctl set interface te-1/1/4 options:cdr-admin-state=true

Disable the CDR function on interface te-1/1/1~te-1/1/4.

admin@PICOS-OVS$ovs-vsctl set interface te-1/1/1 options:cdr-admin-state=false
admin@PICOS-OVS$ovs-vsctl set interface te-1/1/2 options:cdr-admin-state=false
admin@PICOS-OVS$ovs-vsctl set interface te-1/1/3 options:cdr-admin-state=false
admin@PICOS-OVS$ovs-vsctl set interface te-1/1/4 options:cdr-admin-state=false

Remove the CDR function on interface te-1/1/1~te-1/1/4.

admin@PICOS-OVS$ovs-vsctl remove interface te-1/1/1 optionscdr-admin-state
admin@PICOS-OVS$ovs-vsctl remove interface te-1/1/2 optionscdr-admin-state
admin@PICOS-OVS$ovs-vsctl remove interface te-1/1/3 optionscdr-admin-state
admin@PICOS-OVS$ovs-vsctl remove interface te-1/1/4 optionscdr-admin-state