how data is placed in to a pseudowire

[sinbad_sinbad]

hi,

how is data is placed on to the pseudowire coming from the

attachment circuit.

|-------ac---| |--------pw--------|  |-----ac------|

ce ---------pe ----------------- pe ---------- ce

[saurjosh]

AToM encapsulates Layer 2 frames at the ingress PE and sends them to a corresponding PE at the other end of a pseudowire, which is a connection between the two PE routers. The egress PE removes the encapsulation and sends out the Layer 2 frame.

The successful transmission of the Layer 2 frames between PE routers is due to the configuration of the PE routers. You set up the connection, called a pseudowire, between the routers. You specify the following information on each PE router:

•The type of Layer 2 data that will be transported across the pseudowire, such as Ethernet, Frame Relay, or ATM

•The IP address of the loopback interface of the peer PE router, which enables the PE routers to communicate

•A unique combination of peer PE IP address and VC ID that identifies the pseudowire

HTH

Saurabh

[Giuseppe Larosa]

Hello Sinbad,

assuming that the appropriate signalling session is up and running in the forwarding plane the user data frame is placed within an MPLS PDU with a label stack of two labels:

the more external MPLS label is that of the LSP with destination = loopback IP address of remote PE node.

The inner MPLS label has been provided by remote PE node on the targeted LDP session and represents the specific pseudowire service.

The more external MPLS label is changed at each MPLS router hop and is popped (removed) on the penultimate hop (the router before the remote PE node).

The internal VC label does not change on the path and acts as service discriminator on the remote PE node and allows it to send received frames ouf of the correct L2 access interface to the correct L2 CE.

Hope to help

Giuseppe

[shivjain]

Hi Sindbad

The implementaion could be found in the below mentioned link:-

http://www.mplsvpn.info/2011/12/implementation-of-eompls-ethernet-over.html

regards

Shivlu Jain