Editing Wiretapping (section)

===Location data===
[[Mobile phone]]s are, in [[surveillance]] terms, a major liability. 
For mobile phones the major threat is the collection of communications data.<ref>{{Cite news |url=https://www.usatoday.com/story/news/nation/2013/12/08/cellphone-data-spying-nsa-police/3902809/ |title=Cellphone data spying: It's not just the NSA |last=Kelly |first=John |date=2013-12-08 |work=USA Today |access-date=2014-07-22 |url-status=live |archive-url=https://web.archive.org/web/20140722070610/https://www.usatoday.com/story/news/nation/2013/12/08/cellphone-data-spying-nsa-police/3902809/ |archive-date=2014-07-22}}</ref><ref>{{Cite web |url=https://www.aclu.org/protecting-civil-liberties-digital-age/cell-phone-location-tracking-public-records-request |title=Cell Phone Location Tracking Public Records Request |date=2013-03-25 |website=American Civil Liberties Union |access-date=2014-07-22}}</ref> This data does not only include information about the time, duration, originator and recipient of the call, but also the identification of the base station where the call was made from, which equals its approximate geographical location. This data is stored with the details of the call and has utmost importance for [[traffic analysis]].

It is also possible to get greater resolution of a phone's location by combining information from a number of cells surrounding the location, which cells routinely communicate (to agree on the next handoff—for a moving phone) and measuring the [[timing advance]], a correction for the speed of light in the [[Global System for Mobile Communications|GSM]] standard. This additional precision must be specifically enabled by the telephone company—it is not part of the network's ordinary operation.