Re: EPC backhaul networks

[Owen DeLong <owen () delong com>]

On Jan 30, 2011, at 10:09 AM, Mikael Abrahamsson wrote:

> 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.
It's also easier to troubleshoot when something goes boom.

Owen