Cisco Small Business SRP500 limiting bandwidth

[Texashiker]

We have a T1 connected to a Cisco Small Business SRP500, with which we are getting anywhere from 0.3 - 1.3 on the download and close to 1.2 on the upload. Most of the time we are not getting anywhere near T1 speeds, maybe 1/3 - 1/2 a T1.

ATT tech said its probably everyone else in the building causing the slowdown. But even when I am the only one in the building, traffic through the SRP500 is a lot slower then straight into the router.

When I bypass the Cisco Small Business SRP500 and plug a laptop directly into the AT&T supplied router where the T1 connects, I get around 3 - 4 meg upload and download.

What is it about the Cisco SRP500 that makes computers behind it run so much slower?

 

[spidey07]

Likely a duplex mismatch. Make sure all ports are set the same when connected. Force one side 100/full you must make sure the other side is 100/full, not autonegotiate or you'll get a duplex mismatch and extremely poor performance.

Also, single T1 cannot be faster than 1.5 Mbs.

 

[Texashiker]

Likely a duplex mismatch. Make sure all ports are set the same when connected. Force one side 100/full you must make sure the other side is 100/full, not autonegotiate or you'll get a duplex mismatch and extremely poor performance.

Also, single T1 cannot be faster than 1.5 Mbs.

Thx spidey, I think the issue has been resolved.

It was a mismatch alright, but an MTU mismatch. With the MTU set to auto, speeds were terribly slow.

When the MTU was set to 1500, download speeds went from .3 to 1.2.