Someone's hijacking my bandwidth!

Question

I have a little app called Menu Meters, which allows you to see the vital stats of your computer in your menu bar. The network monitor is showing that data is being downloaded through my AirPort at a constant stream of approximately 200 KB/second, sometimes more. I've quickly downloaded another little app called Net Monitor, and its more useful accompaniment Net Monitor Sidekick, but I don't understand much of what they're telling me. Net Monitor Sidekick shows a list of IPs and addresses, some in red and some in black, most of which I don't recognise. I've ordered them by "In Speed". login.keycom.co.uk, the address of my ISP that I have to login to every time I want to use the internet (yes, I'm at university) is downloading at 145 KB/s through port 1451, storage5.badongo.com is downloading at 110 KB/s through a private port, and so on. Doing whois and lookup on these addresses either come up with "refused" or a bunch of stuff I don't understand. This is very worrying - who knows what these people are doing to my computer? And they're using up so much bandwidth, all the time!
On a related note, I've noticed that my iSight camera sometimes comes on randomly - any clues as to why this is? Is it just a glitch, or is someone taking pictures of me remotely while I work? :S Virus scans have come up with nothing...
Any help or advice would be much appreciated.

Answer 1

Bacchus,
You mentioned being connected to the univ network. Assuming your connected via a RJ45 ( fat telephone type connector ) ethernet cable and not wireless, what you state could be true.
But only if the univ is using older shared ethernet hubs or coax cable network, and not current switched ethernet hubs.
The reason being, shared ethernet hubs ( or coax cable ) networks flood the local (lan) network because that shared networks doesn't know exactly what port on what switch your computer is connected to. So it floods all ports and then every computer on that lan has to look at EVERY packet on the net to see if its for it or not, if it not it trashes the packet and waits for the next packet.
If your on a shared net, what you report can be true, massive bandwidth usages, even if you are not sending or receiving anything. If in a few rooms down, someone is downloading files and your on the same lan network, your system will assign resources to EVERY packet on that network to see ifs for you or not.
Comcast networks uses shared lan networks, AT&T dsl does not. Try looking/browsing for other computers/printers on your shared networks and you'll see others on that local lan network.
AT&T uses a dedicated link from your house to the Central Office (CO) to a multiplexor. Switched hubs keep a map of what computers are attached to which ports and will only send packets destined for you.
Now if you really think someone is one your machine, find the Terminal in Utilities directory and open the terminal and type is ;
hostname% who
this will report all the users logged onto your machine at that time.
example below
hostname:~ username$ who
miked console Oct 9 12:59
miked ttyp1 Oct 9 13:00
debbym ttyp2 Oct 9 14:10
two users are logged in miked, and debbym
Check the command 'last' for past users that have logged into your mac.
example below
hostname:~ username$ last
miked ttyp2 Thu Oct 9 14:10 still logged in
debbym ttyp2 Thu Oct 9 14:10 - 14:10 (00:00)
miked ttyp1 Thu Oct 9 13:00 still logged in
miked ttyp1 Thu Oct 9 13:00 - 13:00 (00:00)
miked console hostname.local Thu Oct 9 12:59 still logged in
reboot ~ Thu Oct 9 12:57
shutdown ~ Thu Oct 9 09:27
miked ttyp1 Thu Oct 9 09:12 - shutdown (00:15)
miked ttyp1 Thu Oct 9 09:12 - 09:12 (00:00)
miked console hostname.local Thu Oct 9 09:11 - 09:27 (00:15)
reboot ~ Thu Oct 9 09:11
shutdown ~ Wed Oct 8 11:49
Good luck