Talk:Pen register

Name Derivation
Why is this sort of device called a "pen register"? Where is the name derived from? —Preceding unsigned comment added by 35.10.230.213 (talk • contribs) 22:45, 26 February 2007
 * I was wondering the exact same thing. Quickly googled around but couldn't get a fix on the origin. Definitely something to add to the article, though. --jibun≈παντα ρει≈ (keskustele!) 04:26, 9 July 2007 (UTC)
 * I came here looking for the same thing. The article needs an etymology section. Sadly, I too don't know the origin of the term myself. 86.56.40.172 (talk) 05:31, 5 March 2008 (UTC)
 * I googled and I've found it! According to http://www.brookings.edu/papers/2001/1003terrorism_swire.aspx:
 * The term "pen register" comes from the old style for tracking all of the calls originating from a single telephone. At one point, the surveillance technology for wiretapped phones was based on the fact that rotary clicks would trigger movements of a pen on a piece of paper. Police could then read off the numbers dialed on the phone. Although technology has changed, we still call the list of phone numbers dialed a "pen register."
 * Is it ok to just add that sourced quote to the article or should one entirely write new sentences that contain the same information? 86.56.40.172 (talk) 05:44, 5 March 2008 (UTC)

The above quoted origin for the term is right but fails to track back to the origin. The origins of the term predate dial telephone service and law enforcement use of the technology. I edited the text to give the broader but archaic definition of pen register, along with its origins in telegraphy. Douglas W. Jones (talk) 18:15, 27 September 2011 (UTC)

US Government surveillance
"Pen register" in the news (CNET): http://news.cnet.com/8301-13578_3-57596791-38/fbi-pressures-internet-providers-to-install-surveillance-software/ — Preceding unsigned comment added by 189.169.118.107 (talk) 14:56, 5 August 2013 (UTC)

Merge Pen trap into this article
I came upon the article pen trap, which has "Multiple issues," including that is was orphaned. As I started creating links to the pen trap article, I came across "Pen register," which seems to be exactly the same device, with a slightly different name. Before spending more time improving the pen trap article, I would like to know if all of the information should be put into one article. Comfr (talk) 21:08, 6 January 2015 (UTC)
 * I think that the two pages could helpfully be merged; Pen trap is more up-to-date, but Pen register is more historically complete, and they could show a continuum of ideas and applications. Klbrain (talk) 19:56, 1 August 2017 (UTC)
 * Actually, a trap and trace device is something else. It's something attached to an incoming phone line to prevent "release", so the caller can't hang up. In an electromechanical exchange, technicians could then manually follow the path back through the switch to get the calling number. Huge pain. A not very good source for this.. John Nagle (talk) 23:27, 15 October 2018 (UTC)

Added photo of a pen register
Added a close up photo of an actual pen register. This Bunnell brass and cast iron wind up device seems to be the final development in pen registers. The next step, in the 1970s, was the "dialed number recorder" with electronics and a cash register type printer. John Nagle (talk) 20:54, 9 October 2018 (UTC)

Can I use number for what
WhatsApp registration 102.89.46.156 (talk) 03:50, 16 July 2023 (UTC)