Prior to standardized CAMEL control of the Short Message Service, IN control relied on switch vendor specific extensions to the Intelligent Network Application Part (INAP) of SS7.was sent over the Vodafone GSM network in the United Kingdom on 3 December 1992, from Neil Papworth of Sema Group (now Mavenir Systems) using a personal computer to Richard Jarvis of Vodafone using an Orbitel 901 handset.Over time, this issue was eliminated by switch billing instead of billing at the SMSC and by new features within SMSCs to allow blocking of foreign mobile users sending messages through it.By the end of 2000, the average number of messages reached 35 per user per month, SMS was originally designed as part of GSM, but is now available on a wide range of networks, including 3G networks.Besides the completion of the main specification GSM 03.40, the detailed protocol specifications on the system interfaces also needed to be completed.CAMEL allows the gsm SCP to block the submission (MO) or delivery (MT) of Short Messages, route messages to destinations other than that specified by the user, and perform real-time billing for the use of the service.The first action plan of the CEPT Group GSM was approved in December 1982, requesting that, "The services and facilities offered in the public switched telephone networks and public data networks ...
Although most SMS messages are mobile-to-mobile text messages, support for the service has expanded to include other mobile technologies, such as ANSI CDMA networks and Digital AMPS.
Finn Trosby of Telenor chaired the draft group through its first 3 years, in which the design of SMS was established.
DGMH had five to eight participants, and Finn Trosby mentions as major contributors Kevin Holley, Eija Altonen, Didier Luizard and Alan Cox.
The last three words transformed SMS into something much more useful than the prevailing messaging paging that some in GSM might have had in mind.
The material elaborated in GSM and its WP1 subgroup was handed over in Spring 1987 to a new GSM body called IDEG (the Implementation of Data and Telematic Services Experts Group), which had its kickoff in May 1987 under the chairmanship of Friedhelm Hillebrand (German Telecom).