R211x-HP Flexfabric 11900 MPLS Command Reference

201
control-word enable
Use control-word enable to enable the control word function.
Use undo control-word enable to restore the default.
Syntax
control-word enable
undo control-word enable
Default
The control word function is disabled.
Views
PW class view
Predefined user roles
network-admin
mdc-admin
Usage guidelines
The control word field is between the MPLS label stack and the Layer 2 data. It carries control information
for the Layer 2 packet, such as the sequence number.
The control word field has the following functions:
• Avoids packet disorder. In case of multi-path forwarding, packets received might be disordered.
You can configure the control word function so the device reorders the packets according to the
sequence number carried in the control word field.
• Transfers specific Layer 2 frame flags, such as the FECN bit and BECN bit of Frame Relay.
• Identifies the original payload length for packets that include padding.
The control word field is optional, and you can configure whether to carry the control word field in
packets sent on the PW.
If you enable the control word function on both PEs, packets transmitted on the PW carry the control word
field. Otherwise, the packets do not carry the control word field.
Examples
# Enable the control word function for the PW class pw100.
<Sysname> system-view
[Sysname] pw-class pw100
[Sysname-pw-pw100] control-word enable
Related commands
display l2vpn pw-class
description
Use description to configure a description for a cross-connect group.
Use undo description to remove the description of a cross-connect group.