Is it possible to hijack my DSL service...

[eric halfabee]

At work we have 9 Macs connected to the web via a Nokia DSL router and use a service called Jetstream (just their fancy name for DSL) from our ISP Xtra. We have a monthly limit of 3 GB now 5 Gb as we keep going over and thats why this thread.

Our usage always goes over the said amount and apart from the standard email and web browsing not to mention Mac updates (which I try and keep to a minimum by downloading the package and distributing over the LAN), I'm the only one really doing software downloads and uploads as I take care of the Macs and our web page. to me it seems that the usage is way too high and cannot seem to keep under the 3 GB limit.

I was wondering if its possible for someone outside our LAN to sort of hijack our bandwidth, ie have access to our settings and passwords or whatever and help themselves to our MB's etc?

If so does anyone know of away I can monitor if this is happening?

Cheers

eric

[Lycander]

Get one of those simple Linksys routers, make sure it supports DSL because there's extra authentication (and not just plug and play) for DSL connection to work.

The router has a web based control panel where you can block WAN access, basically anything outside your network. It almost gaurentees that only people on your LAN have access to the DSL connection.

Generally speaking though, it's not likely for someone to hijack your connection, they'd need a connection to begin with. What is possible though, is for a malicious program to get installed and execute itself. It may not be harmful and actually very quiet and subtle, but it may use that infected computer as a "slave" for purposes such as DoS attacking other systems, or sending spam.

Then again, it's Macs you're dealing with right? No worries about viri or worms?

[eric halfabee]

Cheers Lycander

Unfortunately we have to have the Nokia one as its part of our deal with the ISP. I think I can get access to the Nokia control panel so I'll see what I can find.

Anyone know of software for measuring bandwidth usage?

eric

[eric halfabee]

Here's a screenshot of the Nokia main page.

eric

[rbuenger]

Ok, I suggest you to download darkstat 2.6 for OS X. This app is a statistic sniffer that analyse your network traffic and can do some usefull thinks like showing you total bandwidth in and out or what ist often very interesting it can show you where your bandwidth has gone. So you can see how many MB's you used for Mail or for this board.

What darkstat can't do is showing you if some has hijacked your line. But you can compare the bandwith you used with the one you have to pay for

And I would suggest you another very good app: HenWen is a nice GUI for the included snort NIDS package that analyse your networktraffic searching for intrusions and thinks that shouldn't be there. With some Unix knowledge you even can blow this up to a realtime alerting and monitoring system with database storage...

[brianleahy]

Are you by any chance using wireless networking? That would provide an avenue of hijacking.

[macmasta]

how would darkstat display all the traffic on the network? you'd have to have it installed on the router the get this function. dont think you can install it on a nokia router

[rbuenger]

No, you just install darkstat on your Mac under OS X. Darkstat then sniffs all packets this Mac transfers. So if you use multiple computers you have to install it on every of this computers.