Here is an over view of our network design:
We use Metero Ethernet.
2800 Series Router
3750G (Central Office) Internal IP Routing
3750G (Multiple Remote sites) IP Routing
Yesterday a Network Engineer from AT&T visited our site and suggested that we would probably get faster throughput to the ISP if we replaced the 2800 series router with another 3750G and allowed it to route the traffic to the ISP. I don't know enough about 3750 and 2800 to agree or disagree with his assessment so I would like to get opinions from the knowledgable folks on this board. Do you guys agree with him and why?
Thanks for the help.
In terms of throughput the engineer was right ie. you will get more from a L3 switch such as the 3750 than you will with the 2821. However the router can provide more functions than the L3 switch, NAT being one of them as Giuseppe mentioned. Equally important is QOS where a router has a much more fully featured toolset than a switch. Often on Metro ethernet connections you need to shape the bandwidth and switches in general do not support shaping.
So it is a tradeoff. If you don't need the extra features provided by a router then yes go for a switch although it would be interesting to know what ASA model you have in terms of throughput as the switch might not be much of a gain. Bear in mind also that Cisco do a 3750 ME switch (ME = Metro Ethernet) which has more QOS features than the standard 3750.
if your C2800 is not doing NAT or other software bases features you can have a performance gain in using a multilayer switch instead of the ISR router.
you can see raw performance of routers in the attached pdf a C2800 can handle 50 to 100 Mbps of traffic in total so it is not able to handle a true 100 Mbps handoff
A C3750G can do
I would tend to agree with this statement. I can't back it up with numbers, only personal experience. I prefer to terminate Ethernet hand-offs on Switches and in some cases ASA's.