P2P can effect an entire network because it has the potential to flood the entire layer2 network with scanning and trying to establish connections to other users. This doesn’t always happen, but it has been known to happen. The best way around that is to set up proper user isolation on the layer2 network.
It will also effect upload and download speeds, as a torrent by default will use everything it possibly can, if upload is saturated then download is effected since requests cannot make it to the internet in a timely manner, adversely effecting other traffic.
CPU is possible but not as likely as the CPU on most RBs is able to handle a lot of traffic, but you would have to be looking at usage in order to determine that and see.
So if i have Layer 2 user isolation on the hotspot, and i have 30 users on my Ubuquity AP or Mikrotik AP, will the one or let say 20 user using uTorent, with all users in 0.5/.250 down/up package bring the entire hostspot network down?
Will hotspot only give to those uTorrent users max their bandwith, and thats it. ?
How to solve this? i want people to user uTorrent but restrict that, so they wont effect others on the hotspot.