Report of the Independent Surveillance Review
9
neutral.20 As part of their routine business processes, CSPs retain information on their
customers and the use of their services, such as recording the telephone numbers called
by a customer to allow itemised billing. Both CSPs and ISPs also hold names, addresses
and bank details in order to bill customers, and they monitor and retain information
about traffic passing across their networks to help improve the services they offer.21
1.16
Regarding the physical layer, in the past twenty-five years telecommunications services
have expanded rapidly to support cellular and satellite phones and wireless connection
to the Internet, in addition to the physical cables and exchanges that make up the
telecommunications infrastructure. This vast global telecommunications network forms
a vital part of the UK’s critical national infrastructure and is the regular target of attack
by both state and non-state actors.22 The largest telephone network remains that run by
BT which reaches everywhere in the UK (except Hull), while smaller telecommunications
companies have constructed their own smaller ‘figure of eight’ networks connecting
London, Bristol, Birmingham, Manchester and Leeds – paralleling the early deployments
of both canals in the eighteenth century and railways in the nineteenth.23 These
telecommunications networks include major lines designed to handle many signals
simultaneously, connecting major switching centres or nodes. Traditionally, these lines
were made up of copper cables, though there has been increased investment over the
past ten years in national fibre-optic networks, which are able to send much larger
amounts of data over longer distances. Satellite links provide a relatively small part
of the international bandwidth; the preferred choice for CSPs to transfer information
internationally has been to invest in submarine communications cables, as shown in
Figure 1 – most of which today are fibre-optic cables.
20. The definition of ‘telecommunications service’ is described in Section 2 of the Regulation
of Investigatory Powers Act 2000. The Communications Act 2003 also adopts a broad,
technology-neutral definition (in Section 32), but which is narrower than that used in the
Regulation of Investigatory Powers Act 2000.
21. ISC, Access to Communications Data by the Intelligence and Security Agencies.
22. ISR Panel visit to GCHQ, December 2014.
23. Electronic Communications Resilience and Response Group, ‘Telecommunications
Networks – a Vital Part of the Critical National Infrastructure’, Version 1.1, <https://
www.gov.uk/government/uploads/system/uploads/attachment_data/file/62279/
telecommunications-sector-intro.pdf>; The Economist, ‘The Truly Personal Computer’.