Random Net dies

happened before when i was @ home and it stoped when i went to college. It has start back up again and is pissing me off. Randomly my internet jsut decides to die while it still works for others on the network. do i reboot and it works again. usually happens when im running mIRC and bittorrent i think but i cant really say for sure it has only happened twice before.. and i torrent alot so i dont know why it would start up now. how do i fix this