L3 switch routing between "routed ports" performance?

lascumbres · ‎11-17-2008

Here's a question I am pondering. Layer 3 switches are better at InterVLAN routing than routers. But is this still true if a Layer 3 switch has to route between "routed ports" (ports with the "no switchport" command)?

Dorothea

Jon Marshall · ‎11-17-2008

Dorothea

L3 switches can route between routed ports and the performance is still roughly the same as it is when it is a switchport. When you say L3 switches are better than routers i assume you mean better in terms of performance ?

Jon

lascumbres · ‎11-17-2008

Yes, I mean performance. Our 2821 router has a routing performance of kpps, whereas our 3560 switch has of mpps - which is an order of magnitude difference.

I was just wondering, because all docs I could find about L3 performance only ever speak of InterVLAN routing and I wondered whether routed ports have some other mechanism involved.

Btw, yes, I just tested that routing between routed ports works.

Doro

Mohamed Sobair · ‎11-17-2008

Hi,

Adding to Jon's , the difference between L3 Switches and routers that it perform Switching at Layer-3, this is done by keeping the Source and destination Mac of the routed packet along with it TTL value. so the first packet is routed according to normal routing lookup and then its Switched according to the above.

HTH

Mohamed