i just signed up to a data plan and one of its clauses states that if i use my phone as a PC modem, my operator will charge me extra per kB. am i correct that in order to use my N900 as a PC modem, i need to setup bluetooth DUN? how would my operator know that i'm using my phone as a PC modem? is there a way to get around it if they could really find out?

you would use extra data when using it as modem, more data used when you are on for short time compared to mobile usage.

if you keep it light usage then should be ok

well, thanks. i'm not actually worried about my usage cuz i probably won't use it as a modem. my main question is that how do they find out if i'm using my phone as a modem?

The most common way of detecting NAT is monitoring TTL, TCP fingerprinting and monitoring browser agent string.

What's your operator? I'm noticing that T-Mobile USA's 'unlimited' data plan truly is unlimited. . .

None of which would be particularly effective or likely to be done by the carrier I would have thought.

FWIW, I use mine here in the T-Mobile UK as a modem all the time. My 'unlimited' internet usage has a fair usage policy of 1GB. I have gone over this, and no one cared.

I think it'd take more effort than what little gain they'd get by catching you out.

ye I agree with christye, It's probably just a scare tactic. They just say things like that so the average joe thinks "well Im not doing that then". It does make me wonder though, how do they think the average person is going to be able to setup the n900 as a modem? It's not like clicking a button on and even if it was most people cant setup there home wifi let alone one on a phone!

T-mobile have loads of "rules" like no video streaming but you can still do it...

I've been using N900 as a modem on Vodafone Spain, and i've had no problems, except for an sms i recieved informing me i can not use p2p. And I stoped using it just in case...

@Spotfist: Indeed you just need to click a button to use your N900 as a modem. At least in ubuntu, but it can't be that hard on windows either.

I use my N900 as a PC modem with Vodafone Spain and i have no problems for do it. The company especifies on his contract that isn't allowed but, since now, i have no extra charging.