XBOX 360 not connecting to XBOX live but connecting to WiFi network

Looks like it could possibly be your router config. Did it work previously then stop either randomly or after an update? There's some surprisingly sane information about ICMP here (ignore the "Best Answer" and look at the other longer one).

If you know your way around a router then you could stick the xbox in the DMZ. If that solved your problem you could be pretty sure your router config is the issue and could then refine it from there.

It would be worth trying a wired connection also, if you could borrow 20m of cat 5 off someone.

For FPS games your ping will be far too high.

However the bigger issue is the traffic shaping they perform when you try to play. Having played with a mobile broadband connection (Three - a UK company) for 4 weeks, I've discovered that regardless of how little bandwidth your game uses - say 3k/second, the network will cut you off if you exceed even 2k/second after about 1 minute.

Presumbly they have some form of neural network or learning software in place that blocks your UDP packets after a set period. It may not be the same on HughesNet but I'd be wary.

It's crazy that you can download files, browse 500k per page websites like Flickr but they won't let you stream far less bandwidth for games.

The solution I use is to host an adhoc wifi network on Windows 7. Then once the game is blocked, I kill all the connections to that game using Netlimiter. The number of disconnects I get generally drops after peek hours, but they're very aggressive with the "learning" and blocking of the gaming traffic during peak hours.

It's ugly and extremely cumbersome but does work slightly better than a reconnect via the modem.

You might also want to get an antenna for the 3G USB modem, either a clip one or an outdoor one.