Skype is a popular VoIP (Voice over IP) application that allows users to make free VoIP calls to other Skype users. The Skype company also provide charged services, thus providing them with a revenue stream, that allow users of the Skype software to call landline and mobile phones. Skype can also be used for group video call.
It is a feature of Skype that a machine running it may become a 'supernode'. This means that it may act as an exchange, routing calls between other Skype users, and the amount of traffic may be substantial - this should be of concern to University departments and Colleges because of the University's traffic-related usage charges.
Currently each College and department is charged for part of the cost of using the national academic network, JANET. That charge is based on the percentage of the University's aggregate network traffic used. The use of Skype (and other applications with similar properties) can cause a dramatic increase in network traffic and can therefore result in an increase in a department's or a College's charge.
The University Computing Service does not ban Skype. However, individual departments and Colleges may impose their own bans on the use of Skype, and some have done so.
Recommendation
The Computing Service recommends that certain steps be taken if using Skype. To minimise excessive network traffic and the the risk of abuse Skype should be configured as follows.
- Untick the Start Skype when the computer starts box.
- Untick the Sign me in when Skype starts box, as that means anyone could use your Skype account from the computer you are on in the future without you knowing about it