Hi Georgi,
These terms all start to run together don’t they?
First, let’s talk about AToM vs EoMPLS. EoMPLS is AToM that is transporting a specific protocol (Ethernet). AToM is capable of transporting other layer 2 protocols as well, so it has a more broad meaning. The confusion is that most people use Ethernet at layer 2, so in that case EoMPLS and AToM appears to be the same thing. Think of it this way: EoMPLS is a specific kind of AToM just like a Poodle is a specific kind of Dog.
Now let’s talk about L2TPv3 vs EoMPLS. These are both trying to accomplish the same thing: Extend a layer 2 boundary across a WAN, but they use different protocols to do it. Each has their own pro’s and con’s. Here are a few highlights:
EoMPLS
Pros:
Wide hardware support
Better traffic engineering control
Cons:
Requires end-to-end MPLS configuration, which is usually more expensive to the customer
L2TPv3
Pros:
Any IP based Internet connection is supported (DSL, Cable Modem, etc)
Less expensive than MPLS
Cons:
Newer technology, so not as widely supported as EoMPLS