Internet slow on network

I would be good to use some speed test from you ISP to test connection speed to your ISP directly. With using speedtest.net you test much longer path and your ISP can not guarantee speed over some external network.
Simplest and cheaper test is to disconnect everything for your internet connection and test the speed with only one "trusted" computer at the time when the problem arises. In this way you can at least find if the source of your problems is inside of outside of your network.
To get more data, you would need a router or firewall that tracks the traffic from your network and the source of it.

Try few and always choose server closest to your location

http://speedtest.comcast.net/

Here you have list of many
http://pcsupport.about.com/od/toolsofthetrade/tp/internet-speed-test.htm

The best way is to use the speed test designed by your IPS

DSL is normally a shared line, so at busy times you are less likely to get fast downloads as everyone else around you (sharing the same trunk) is also downloading.
When is this happening - what times?
Have you checked with your ISP - they are your first port of call as they are the people selling you the broadband and managing the network.  We cannot diagnose their network.

If I ping www.google.com -t and monitor it I get response times if around 30ms which is normal but then other times it jumps up to anywhere between 100 to 500ms for a while the drops down and them back up.

I was hoping for some tool I could run on the network that could tell if a computer was sending and receiving large amounts  of data

Thankyou.

The thing is it is not consistent. users will says its great one minute and bad the next. No time is better or worse.

I really dislike random issues

Downloading and browsing are measured differently, your ISP should be able to assist you if you experience slow browsing during pick hour.

As mentioned by an expert, the download might be slow during pick hour as the line is shared, but browsing is normally prioritised.

If the "slow downs" last long enough you could write a script to alert you when your ping to google exceeds a certain value, then turn on Wireshark . . . This assumes that you can write a script to notify you and that you have a way to mirror all traffic to an analyzer like Wireshark. Another option -- if you cant mirror all your internet traffic -- would be to install a free or cheap proxy and proxy all internet traffic through a machine and run wireshark on that machine.

All that said, internet "slow downs" can be difficult to pin point. But it is a good idea to have the ability to look at all your ingress/egress traffic. At the very least, I would have an IPS/IDS set up so that you have some sort of idea what's coming and going.

Good luck,
Steve

Online network diagnstics (especially intermittent drops etc)
http://netalyzr.icsi.berkeley.edu/

Remember the speeds an ISP provide for most services is the max you can get, not a guarantee. There will always be fluctations, especially as more users are on the internet (be it your network or even on your same ISP in your area). Plus you cannot controller the speeds the other end are experiencing at a given point in time.

It would take couple of cities of dsl users to saturate 200Gbps UC berkeley network....

Are there specific times that this issue appears to occur?

We have found previously on our networks that if this is occuring during lunch time etc then it may be news sites. a lot of news sites (particularly australian ones) have flash animations on the site and adds etc as well as youtube.

you get users who open up 20 tabs each and that continually loads these images 20 times for each user. depending onthe amount of users you have connected to said network this can be a monumental drain.

do you have any software to monitor internet usage stats? this could be a big clue for you