Switching design

carl_townshend · ‎03-13-2008

Hi all, at my workplace we have 2 core multilayer switches providing routing and vlans, I guess its a collapsed backbone, all my edge switches connect to both of these core switches. The plan is to have another building 200 meters away with quite a few networked devices in there, I can see 2 options here, install multilayer switches in the new building with vlans terminated on there, and then route to the core, or I set the vlans up on the core switches as they are now and keep it all at layer 2 from the edge, whats is the best design here ?

Amit Singh · ‎03-13-2008

Hi Carl,

How many users in the new building. If the user density is huge in number then, it make sense to put another multilayer switch as the distribution layer for this building and do the routing locally and then connect the distribution switch to the core over the fiber.

If you have a less number of users in the new building and you have to span the same vlans to the new buliding then you can simply connect the edge switches directly to the core switches.

HTH,

-amit singh

carl_townshend · ‎03-13-2008

Cheers amit, so what level of users should I decide to change to the distributed routed model ?

jeff.velten · ‎03-14-2008

I believe the rule of thumb is that if you need to have multiple VLANs in the new building, then use a Layer 3 switch.

Take this with a grain of salt though, I'm only on my 2nd cup of coffee...