NHSnet was a private wide area network

Wide area network

A wide area network is a telecommunication network that covers a broad area . Business and government entities utilize WANs to relay data among employees, clients, buyers, and suppliers from various geographical locations...

 service used by the National Health Service

National Health Service (England)

The National Health Service or NHS is the publicly funded healthcare system in England. It is both the largest and oldest single-payer healthcare system in the world. It is able to function in the way that it does because it is primarily funded through the general taxation system, similar to how...

 (NHS) in England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

.

NHSnet was managed jointly by BT

BT Group

BT Group plc is a global telecommunications services company headquartered in London, United Kingdom. It is one of the largest telecommunications services companies in the world and has operations in more than 170 countries. Through its BT Global Services division it is a major supplier of...

 and Cable and Wireless and was developed under the aegis of the NHS Information Authority

NHS Information Authority

The NHS Information Authority was part of the UK National Health Service . It was established by an Act of Parliament in 1999. With headquarters in Birmingham, UK, its aim was to bring together four NHS IT and Information bodies to work together to deliver IT infrastructure and information...

. However the standards of service varied widely throughout the NHS due to different local practices and levels of equipment. NHSnet was succeeded by N3

N3 (NHS)

N3 is the national broadband network for the English National Health Service , connecting all NHS locations and 1.3 million employees across England. In 2004, BT was awarded the contract to deliver and manage N3 on behalf of the NHS....

 in 2006. It is sometimes referred to (by a sort of retrospective nomination) as "N2".

Connections to NHSnet were strictly controlled by the NHS Information Authority, which specified the security required and data protocols allowed under its 'Code of Connect' agreements. Similarly, it controlled access to or from the Internet, including email, through managed gateways.

Organisations wishing to provide information or applications to their NHS partners over NHSnet had a choice of applying for their own Code of Connection, which required a considerable investment in time (typically 6 months), effort and infrastructure; or partnering with one of the restricted number of organisations (BT, Cable and Wireless and ioko

Ioko

ioko is a systems integration and IT services company that designs, builds and runs digital media platforms for Media and Entertainment companies worldwide. It specialises in application development, media systems integration and dedicated managed services and mostly known for its involvement in...

) able to use their own Code of Connect for these purposes.

NHSnet admin passwords were exposed, during the attack of Lulzsec in June 2011.