Editing SMS (section)

=== GSM ===
{{Main|Short message service technical realisation (GSM)}}
The ''Short Message Service—Point to Point (SMS-PP)''—was originally defined in GSM recommendation 03.40, which is now maintained in [[3GPP]] as TS 23.040.<ref name="GSM 03.40">{{cite web|url=https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=141|title=Technical realization of the Short Message Service (SMS)|id=GSM TS 03.40|access-date=3 December 2022|archive-date=3 December 2022|archive-url=https://web.archive.org/web/20221203215922/https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=141|url-status=live}}</ref><ref>{{cite web|url=https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=747|title=Technical realization of the Short Message Service (SMS)|id=3GPP TS 23.040|access-date=3 December 2022|archive-date=7 December 2022|archive-url=https://web.archive.org/web/20221207054608/https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=747|url-status=live}}</ref> GSM 03.41 (now 3GPP TS 23.041) defines the ''Short Message Service—Cell Broadcast (SMS-CB)'', which allows messages (advertising, public information, etc.) to be broadcast to all mobile users in a specified geographical area.<ref name="GSM 03.41">{{cite web|url=https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=142|title=Technical Realization of Short Message Service Cell Broadcast (SMSCB)|id=GSM TS 03.41|access-date=3 December 2022|archive-date=3 December 2022|archive-url=https://web.archive.org/web/20221203215908/https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=142|url-status=live}}</ref><ref>{{cite web|url=https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=748|title=Technical realization of Cell Broadcast Service (CBS)|id=3GPP TS 23.041|access-date=3 December 2022|archive-date=3 December 2022|archive-url=https://web.archive.org/web/20221203215908/https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=748|url-status=live}}</ref> [[Cell broadcast]] is the technology behind [[Wireless Emergency Alerts]] in the US which is used for public safety messages and AMBER alerts,<ref>{{cite web|url=http://www.fcc.gov/guides/wireless-emergency-alerts-wea |title=Wireless Emergency Alerts (WEA) |date=6 May 2014 |publisher=FCC.gov |access-date=2015-07-15}}</ref><ref>{{cite web |url=http://www.eena.org/ressource/static/files/2011_11_17_one2many.pdf |title=Cell Broadcast ; One2many |publisher=Eena.org |access-date=2015-07-15 |archive-date=2015-09-23 |archive-url=https://web.archive.org/web/20150923234130/http://www.eena.org/ressource/static/files/2011_11_17_one2many.pdf |url-status=dead }}</ref> and similar public safety messages in [[Cell broadcast#Public warning implementations|other countries]]. These messages are similar to SMS messages.

Messages are sent to a [[short message service center]] (SMSC), which provides a "[[store and forward]]" mechanism. It attempts to send messages to the SMSC's recipients. If a recipient is not reachable, the SMSC queues the message for later retry.<ref>Gil Held: "Data over Wireless Networks." pages 105–11, 137–38. Wiley, 2001.</ref> Some SMSCs also provide a "forward and forget" option where transmission is tried only once. Both mobile terminated (MT, for messages sent ''to'' a mobile handset) and mobile originating (MO, for those sent ''from'' the mobile handset) operations are supported. Message delivery is "[[best effort]]", so there are no guarantees that a message will actually be delivered to its recipient, but delay or complete loss of a message is uncommon, typically affecting less than 5 percent of messages.<ref>{{citation |url=https://cs.uwaterloo.ca/research/tr/2007/CS-2007-42.pdf |title=Design and Implementation of a Short Message Service Data Channel for Mobile Systems |last=Oliver |first=Earl |access-date=March 14, 2022 |archive-date=January 26, 2022 |archive-url=https://web.archive.org/web/20220126180516/https://cs.uwaterloo.ca/research/tr/2007/CS-2007-42.pdf |url-status=live }}</ref> Some providers allow users to request delivery reports, either via the SMS settings of most modern phones, or by prefixing each message with *0#.<ref>{{Cite news|date=December 9, 2018|title=Text Message Tips (not sent or received)|url=https://community.o2.co.uk/t5/How-to-Guides/Text-Message-Tips-not-sent-or-received/ba-p/1179723|access-date=September 28, 2021|website=community.o2.co.uk|language=en|archive-date=September 28, 2021|archive-url=https://web.archive.org/web/20210928142837/https://community.o2.co.uk/t5/How-to-Guides/Text-Message-Tips-not-sent-or-received/ba-p/1179723|url-status=live}}</ref>