simultaneous internet activity

Does Ubuntu support multiple applications accessing internet simultaneously? The problem I am noticing is that if I am downloading via bittorrent client or synaptics then I cannot surf or send/receive email. I am experiencing quite a slow internet speed - regardless of application my download speed seems to be capped around 50kbps - I don't think this is necessarily being caused by Ubuntu (I am on an old exchange so I do not get a fast speed - typically 2mbps but slows during daylight hours) as Speedtest has shown that I am not actually getting anywhere near my expected speed. So back to the question at hand - I am not sure if the limitation on simultaneous activity is purely that I have a crap connection or if Ubuntu is causing it. I am currently wirelessly connected so I will try a wired connection at some point to see if that improves matters.