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New Member

Upgrading to Ethernet, but have questions about MPLS?


I'm kind of new to MPLS and just want to know more about the technology, I've read some articles, but just have a few questions.

Our WAN infrastructure composes of ATM and P2P T1s. We will be upgrading to ethernet for bandwidth reasons. MPLS was brought up in the discussion awhile back ago and was not mentioned anymore. Are we to say that ethernet is better then MPLS or are we talking apples and oranges here?

Thank you


New Member

Re: Upgrading to Ethernet, but have questions about MPLS?

Yes my friend. If we talk about OSI 7 Layers, Ethernet is Layer-2 while MPLS runs between Layer-2 and Layer-3. Hence runs on top of Layer-2 technologies like Ethernet, ATM, FR, PPP and HDLC.

CE1----(PE1-----Service Provider MPLS Network------PE2)----CE2

Your CE-end routers (CE1 and CE2) connect to Service Provider PE routers using Ethernet- no MPLS is required on this link. The SP MPLS network can be Layer-2 and Layer-3 MPLS network. In Layer-3 MPLS VPN network, CE routers form adjacency with PE routers while in Layer-2 MPLS VPN network, the CE routers form adjacency with each other.

At the moment, your topology could be looking like this.

CE1----(ATM Network)-------CE2

This is Layer-2 network all the way and hence routing protocols (if any) will form adjacency between CE routers.




New Member

Re: Upgrading to Ethernet, but have questions about MPLS?

Thanks Amit for your explanation. So from what I understand MPLS is more like a technique or configuration that you apply over the technology you choose (e.g. ethernet, ATM, FR). Very well, then our SP may have already implemented MPLS on their network without our CE ever being involved. If this is a true statement, then I wonder what kind of advantage MPLS can provide to the customer?