Layer 2 over MPLS !

[Jonn cos]

Hi all experts.

If an ISP has a customer with 200 branches, and that customer wants all his branches to be provided layer 2 connectivity, means it wants a full mesh at layer 2 just like ethernet, so that there is no need for Tunnels and the client is able to run any protocol at layer 2 like OSPF etc. What method generally an ISP use to provide such service to its customers ? i mean is it VPLS ? or EoMPLS ? AToM ? L2tpv3 ?

Can some one highlight how such a service is provided and what is the recommended method ?

[Ivan Krimmel]

Hi John,

AToM, L2TPv3 are all p2p ways of transmitting l2 information, just like EoMPLS. So if a customer needs to achive point-to-multi-point connectivity and in the end to have Ethernet-like service across an ISP cloud, then VPLS is the preffered solution.

[Jonn cos]

Dear Sir,

Is it correct that VPLS is only supported on 7600 routers ? if thats the case and ISP is using 7200 routers, so should they upgrade to 7600 or is there a workaround that can be temprorarily used to provide VPLS like services ?

[Ivan Krimmel]

John,

the workaround could be a bunch of p2p EoMPLS'es forming a cloud, but that won't scale well and doesn't really substitute all the advantages VPLS has.

As for gear, high-end SP boxes support VPLS - ASR9k, CRS, GSR, and of course 7600. For the full list please consult the Cisco Feature Navigator.

Hope to clarify.