University Data Network (UDN) services

The backbone data network provides a wide variety of connectivity services for University institutions. The network itself is known as the University Data Network and often referred to as the 'UDN' (historically the Cambridge University Data Network [CUDN]).

Note: Much of the information here is written for IT staff with a background in data networking; it is not likely to be of much interest to the casual user.

At a basic level, the UDN connects institutions within the Collegiate University with each other, as well as central services provided by the UIS and other institutions (such as central email and filestore services), and also to Janet. Janet is the UK education and research network, which interconnects higher and further education establishments within the UK and provides connectivity to these organisations to the internet through a number of providers.

Typically, a connection to the UDN is required to make use of many central services, such as the University Telephone Network or University Wireless Service.  To obtain a UDN connection, an institution normally needs to be on the Granta Backbone Network (GBN) — the collegiate university's dark fibre network.

However, the UDN also offers a number of additional services, as well as basic network connectivity. These services are described here (along with links to more information):

• Routed IP data network connection
  The basic, routed IPv4 and (optional) IPv6 connection to the University backbone network and Janet / the internet. An institution's main staff, student and research network will typically use this. A connection has a number of options. It can:
  • be supplied via a PoP switch or a directly-routed BGP connection, which can be provided through UIS-managed router
  • support multicast.
  • use public and private IP addresses; the latter will be linked to Janet via the NAT service.
• MPLS virtual private network (VPN) service
  The MPLS service allows private networks to be built using the existing UDN infrastructure but traffic to be kept logically separate from the normal internet-routed space, except where explicitly interconnected.  This is useful to support wholly-private networks (such as a security system) or internal institutional networks to be extended over the UDN backbone.
• Infrastructure service networks
  These support infrastructure other than traditional computer connections for equipment such as CCTV, BMS (Building Management Systems) as well as the University Telephone Network.
• VLAN services
  To support switched / layer 2 connectivity, the UDN supports a number of VLAN-based services.

Last updated: 3rd February 2021