Skype (http://www.skype.net) is a popular VoIP software product that allows users to make free VoIP calls to other Skype users. The University requires that anyone using Skype on the Oxford network should configure the software as specified in the installation and configuration instructions.
The main reason for the special configuration requirements is that Skype can use excessive network resources in certain cases. This is because a machine running Skype can, without your knowledge or control, act as a 'Supernode' exchange for routing calls between other Skype users. The required measures given in the setup instructions are designed to reduce this possibility.
OUCS has no particular expertise in use or trouble-shooting of Skype. The configuration pages provided are purely to avoid the program overloading the Oxford network. Skype have an FAQ and Support page which covers most common problems.