Editing BT Group (section)

=== Post Office Telecommunications ===
[[File:Telecom_Tower,_London_taken_1966_-_geograph.org.uk_-_807317.jpg|thumb|The [[BT Tower]], then known as the Post Office Tower, 1966 (shortly after construction)]]
In 1969 the GPO, a government department, became the [[Royal Mail|Post Office]], a nationalised industry separate from government. '''Post Office Telecommunications''' was set up as a division of the Post Office, in October 1969.<ref>{{cite web |title=Post Office and British Telecommunications Public Corporations |url=https://archiveshub.jisc.ac.uk/search/archives/a985c70a-8be3-3dfb-83c4-e7f127537064 |url-status=live |archive-url=https://web.archive.org/web/20190306044111/https://archiveshub.jisc.ac.uk/search/archives/a985c70a-8be3-3dfb-83c4-e7f127537064 |archive-date=6 March 2019 |access-date=2 March 2019 |publisher=Archives Hub}}</ref> The [[Post Office Act 1969]] was passed to provide for greater efficiency in post and telephone services; rather than run a range of services, each organisation would be able to focus on their respective service, with dedicated management. By law, the Post Office retained the exclusive right to operate the UK national telecom network, (although since 1914 had licensed Hull City Council to operate its own local telephone network, [[Kingston Communications]]).<ref>{{cite web|url=http://www.kcomplc.com/about-us/our-history/|archive-url=https://web.archive.org/web/20131112125913/http://www.kcomplc.com/about-us/our-history/|url-status=dead|title=KCOM Group: Our History|archive-date=12 November 2013|access-date=6 August 2019}}</ref>

The 1970s was a period of great expansion for the Post Office. Most exchanges were modernised and expanded, and many services, such as [[Subscriber trunk dialling|STD]] and [[International direct dialling|international dialling]] were extended. By the early 1970s, subscribers in most cities could dial direct to Western Europe, the US, and Canada; by the end of the decade, most of the world could be dialled direct. The [[System X (telephony)|System X]] digital switching platform was developed, and the first digital exchanges began to be installed.<ref>{{Cite web|title=Exhibits: System X|url=https://www.communicationsmuseum.org.uk/systemx/|access-date=2021-05-27|website=The Communications Museum Trust}}</ref> The Post Office also procured their own fleet of vans, based on the [[Commer#Commer FC.2FPA.2FPB.2FSpacevan|Commer FC]] model.<ref>{{cite web| title = Dodge Spacevan / Telecom Van (Commer PA and PB vans, Dodge K-series)| work = allpar.com | publisher = Allpar, LLC | url = http://www.allpar.com/squads/spacevan.html | access-date = 2 April 2008}}</ref>

Post Office Telecommunications researched and implemented [[data communication]]s using [[packet switching]] in the 1970s, resulting in the [[Packet switching#EPSS|EPSS]], [[International Packet Switched Service]], and [[Packet Switch Stream]].<ref>{{Cite web |last1=Smith |first1=Ed |last2=Miller |first2=Chris |last3=Norton |first3=Jim |date=2017 |title=Packet Switching: The first steps on the road to the information society |url=https://www.npl.co.uk/getattachment/about-us/History/Famous-faces/Donald-Davies/UK-role-in-Packet-Switching-(1).pdf.aspx?lang=en-GB |access-date= |website=National Physical Laboratory}}</ref>