Most peer to peer software is banned unless otherwise advised. Obviously illegal music / video sharing software is banned. Examples include:
eDonkey, Kazaa, utorrent, vuze, Audio Galaxy, Freenet, Gnutella, LimeWire, Morpheus, Napster, Bittorrent and Toadnode, as well as TV distribution that uses Peer to peer technology, such as VeohTV. (This is not an exhaustive list!)
There are two related issues here.
The first is the issue of University network security and/or bandwidth issues. To minimise the associated problems with this, there is a general ban on peer to peer software. People found using such software will be blocked from the University network.
The second issue is breach of copyright. Many of these programs are designed to easily download and distribute illegal copies of music, video and other data. The act of downloading it is illegal. Being connected to some of these peer to peer networks means you are also acting as a node to distribute media without a licence. This is increasingly being monitored by agents acting on behalf of media companies. There were several cases last year of legal copyright infringement notices served on the University due to the activities of GTC students. Current policy is at minimum the loss of internet access until the matter is resolved, and a fine. Such infringements may result in disciplinary action.
More details can be found at : http://www.it.ox.ac.uk/policies-and-guidelines/peer-to-peer-resource-sharing
Increasingly, legal sources are using peer-to-peer netwroking tools to distribute films and other media. Although this is legal, it is still banned by College regulations due to bandwidth issues.
Kontiki peer-to-peer service ("Kontiki") - which will affect the following programmes (including but not limited to) BBC iMP (iPlayer Download Manager), Sky by broadband Kontiki Delivery Manager, Cinequest Delivery Manager, AOL Hi-Q Delivery Manager, Palm Support, VeohTV, and the Open Media Network.
However, the BBC iPlayer is allowed, as this does not uses P2P technology. See www.bbc.co.uk/iplayer/.
Also the Veoh Web Player would seem to be acceptable, but not the VeohTV application.