Computer Laboratory

Wireless network access

The wireless network is intended to cover the entire William Gates Building and uses equipment rented from and managed by the Computing Service. 802.11b/g/n are supported at 2.4GHz and 802.11n at 5GHz. The physical access points provide more than one logical network, so there are different ESSIDs for different purposes. Some of these are University-wide and are documented by the Computing Service; others are local to the Computer Laboratory.

The JANET Roaming Service: eduroam

The ESSID eduroam offers the JANET Roaming Service, and is available to both Cambridge users and visitors who have appropriate credentials from a participating institution. It is the preferred network for people wanting CUDN connectivity from wireless devices; although the initial setup is non-trivial, once done it will offer very simple roaming throughout the University and at many other institutions world wide. Local users should start here.

The Computing Service Lapwing Service

The ESSID lapwing is network offered by the Computing Service using a captive portal access model. It can be used by anybody with a Raven account, and it is also possible for us to issue temporary tickets for visitors, conferences etc. Documentation is here. All members of staff may issue short term tickets for their guests; longer term and bulk tickets are available from the system administrators or Reception.

The local wireless network

We offer a local wireless network with the ESSID Internal-CL. This is intended for users who need a CL ip address for whatever reason - if that is not the case then you may be better off with eduroam. It provides IPv6, and has the minor advantage over eduroam that packets do not have to travel to the UIS and back again, they stay on a local VLAN. Authentication is similar to eduroam, so local users should start here. Authorisation is based on a CRSID linked to the CL (ie all lab members).

A deprecated wireless network

There is a local wireless network with the ESSID w-107-CB3-0FD. It is deprecated and will eventually be phased out. New users should not be using this network. Wireless LAN connectivity on this network is only available to staff and research students. It uses WPA2/PSK encryption, and individual machines must be registered to use it.

Visitor access

The ESSID wgb offers an "open access" network, giving NAT-based internet connectivity via a Demon ADSL line. In many ways it is similar to the setup many people have at home. The intention is primarily to offer a courtesy internet service for visitors to the building without the AUP constraints of the CUDN and JANET or the need to register. Of course Demon have an AUP too, and we may be forced to put access restrictions on this network if it turns out to be abused.

By the very nature of things, it is also available to members of the department. However it is not primarily intended for making connections back into departmental machines, as all such connections will go out onto the public internet and come back in again through JANET. This is fine for a quick check of Email or some such, but not ideal for long sessions or bulk transfers. The bandwidth of the ADSL link is inherently limited, and is sometimes subject to further throttling by Demon if traffic levels exceed our monthly allowance. It may be necessary to restrict connections back into the lab if such use turns out to cause overload. Please do not use this network simply because it is the easiest.