Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 
New Member

Slow Internet Speeds


I've got a stack of 3750 switches connecting to a PIX 515e then off to an ISPs router...

We have a 20meg link from the ISPs router to the Internet.

But, we are not getting 20 meg speeds when we download anything from the Net. I've done countless download speed tests, and they all give results of around 5meg down and 1meg upload speeds.

I've raised this with the ISP who tell me we're just a low usage site, but sometimes I can see the download speeds of about 27k at times!

They given me a tool that I log into that tells me what speeds we're getting from the ISP and sure enough, the speeds are about 5meg. Every now and then I might see the chart go up to 14meg which is more like it, but this only happens once a month or so.

Internall, we can move large files around from PCs to servers just fine and very quickly.

Does anyone have any idea os to what I can try to get to the bottom of why thingts are slow, maybe a monitoring tool?

Thank You,


Re: Slow Internet Speeds

Hi ,

I am confused here between speed and throughput. If you have ordered 20meg bw then you should get 20meg throughput in both direction

(upload/download )..This is SLA from your provider.

Now speed is no where included in provider SLA..It depends upon window size of source and destination...MTU of all intermediate devices...and few other parameter.

there are few free software to increase window size of pc which help you to see more upload/download speed.

If you are talking about throughput it is entirely your ISP issue. you can simply ask them to have agreed SLA



CreatePlease to create content