EPC backhaul networks

Mikael Abrahamsson swmike at swm.pp.se
Sun Jan 30 12:09:15 CST 2011

On Sun, 30 Jan 2011, Glen Kent wrote:

> I would like to understand why there is a preference for L3 VPNs over L2 
> VPNs for the EPC backhaul networks? We can use both layer 2 and layer 3 
> VPNs for communication between the eNodeB and the MME or S-GW, so why is 
> it that most providers prefer L3 over L2.

Becuase the lessons learnt in the last 30 years or so of networking is 
that large L2 domains are considered harmful. If you subnet them down in 
different vlans, it means for every new vlan you need to configure 
something on the MME/SGW.

It's just easier and safer to break it down into smaller L3 domains that 
you route between.

Mikael Abrahamsson    email: swmike at swm.pp.se

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