"PW Ethernet Control word" header

[TangoAlfa]

Hi All,

Can any one please clear this doubt. Here in below this snip capture of MPLS L2 VPN all header.

Here what "PW Ethernet Control word" header does? even it is optional.

If this header comes whenever we make Pseudo Wire  then how its become optional in MPLS L2 header?

[M02@rt37]

Hello @TangoAlfa 

The reason it's considered optional is that not all implementations or deployments may require the control word. Some networks or services may function perfectly without it, especially if they have other means of achieving sequencing, length indication, or alignment.

When it's stated that it's "always present" in the context of MPLS L2 VPNs, it means that if you decide to include the PW Ethernet Control Word (which is optional), it will be present and used for control information related to the Ethernet payload on the pseudowire.