Having issues with some app apparently trying to do huge automatic updates and repeatedly failing (and retrying). Keeps sucking up large quantities of bandwidth, and I'd like to put a stop to it. Problem being, I have no idea which app (of several that have "silent" background updates) it is.
Open Command Prompt (cmd.exe), execute
and look for 'ESTABLISHED' connections. Add
-n to disable name resolution.
The question is for Windows XP, but I arrived here through google looking for info on later Windows versions. If you're running Windows 7 or later:
- Start Task manager (right click taskbar and choose Task manager)
- Switch to the "Performance" tab
Click "Open Resource Monitor" at the bottom.
Press Win+R and type
Expand the "Network" section and wait for it to update.
I'm guessing this would be similar to sgmoore's Process monitor answer, but we can now do this with a built in tool in windows 8.
That will give you all TCP and UDP ports along with the respective executables involved in the communication.
For a more visual indication indication of your current connections you may want to search for netowrk monitoring tools, or probably have one available already if you are using a personal firewall the likes of Comodo.
Another handy method if you do not have huge network traffic is Sysinternals Process monitor which can be configured to monitor network traffic. It can be left running and should show what applications are accessing the network and the address/ipsite they are calling.
AnVir Task Manager will monitor your network traffic (amongst many other features) and provide all information you're looking for. it will also allow you to quarantine processes (without killing them) to eliminate the culprit.
(beats Sysinternals PE hands down, even in the free version)
I'm a big fan of http://www.wireshark.org/ for packet capture or other network analysis tasks.
If you're using linux, you can use IPTRaf, which is a real-time monitoring application. Checks all connections on all protocols, by port, etc.
If you're using Windows, you might want to check out Ethereal which is a GUI driven monitoring app.
The things I like about IPTraf and Ethereal (as opposed to netstat, which is pretty awesome) is that you can run them for a period of time to see what the hell is going on.
Your question is a big part of the reason that I tend to seek and destroy auto-update processes, and prefer to rely on performing a periodic check for updates myself. I'm capable of running updates once a week or more, without using up RAM forever and ever. :)
So, having said that, one method you might use for nailing down the culprit would be to determine which apps you have installed that are performing background updates (Firefox, iTunes, Notepad++, uTorrent, Google Update, Real Player, Java, etc) and try to use their manual "check for updates" facility and see which of them fails to complete successfully.
However, if you believe that the problem is specific to the actual background update process you might track it down by disabling them one at a time until the problem disappears. I use WinPatrol, but the "msconfig" utility (Start | Run | msconfig) will also allow you to disable those processes. (And more, so use it wisely.)