MPLS L3VPN over VPLS

[maulik.parekh]

Hi All,

I have been wondering if we can run MPLS LDP over existing VPLS service from Service Provider.

What I mean to say is if service provider is providing VPLS service, between the CE routers can I use MPLS so that I can create VRF's on the CE device and hence create L3VPN breakout at the CE devices.

We know that is possible using CarrierSupportingCarrier architecture but there core service provider also provides L3VPN. Is it possible to change it to VPLS ?

I tried this scenario with Point to Point VPWS in GNS3 and it is working great.

I would like to know if we there are any practical challenges that would not allow me deploy such a solution. Also if you could point me to documentation showing such scenario.

Attaching what I tested in GNS3.

[Giuseppe Larosa]

Hello Maulik,

it is feasible but it is not scalable as CSC because the VPLS builds a single broadcast domain so all the customer PE routers would be in a single IP subnet.

So limitations on the maximum number of devices that you can peer in a single IP subnet with the IGP are the first to be hit.

One thing is to have a total number of 200 routers in OSPF area 0, another thing is to have 200 OSPF routers in the same IP subnet this would likely kill OSPF DR device!

With CSC you have a multi tier routed approach and each customer PE just needs to peer to the top SP PE node (peer model).

So the use of some p2p pseudowire to interconnect two customer PE nodes is used, but mapping many sites/POPs over a single broadcast domain on a VPLS is not scalable.

Hope to help

Giuseppe

[maulik.parekh]

Hi Giuseppe,

Thanks a lot for quick reply.

In my case the customer Service Provider (in CSC architecture) is actually enterprise. This enterprise wants more control over its routing than the Service Provider.

Scalability is a concern, I agree to it but currently they have three sites and are not going to grow than 10 in next 10 years

and hence I am planning to use static routes as IGP and then to run MP-BGP over it since, VRF's at the edge is the main requirement.

Will there be any performance issues I may face ?

[Giuseppe Larosa]

Hello Maulik,

if the number of sites is limited to 10 the proposed approach of getting a VPLS service from SP and running MPLS L3 VPN over it will work with no issues.

I recommend to use a dynamic IGP over static routes

Hope to help

Giuseppe

[maulik.parekh]

Hi Giuseppe,

Thanks again for replying.

I recommended the customer use of static routes since the team operating the network is not adequately skilled. I would try to convince them to use IGP but lets see.

What I now need is any documentation showing this scenario as customer might ask for any proofs or case studies for such a thing which I dont have.

Regards,
Maulik Parekh