 SuperJanet3 created new 155 Mbit/s ATM nodes to fully connect all of the major sites at London, Bristol, Manchester and Leeds, with 34 Mbit/s links to smaller sites around the country.In March 2001 SuperJanet4 was launched.The key challenges for SuperJanet4 were the need to increase network capacity and to strengthen the design and management of the JANET network to allow it to meet a similar increase in the size of its userbase.