The GSM is optimized for telephony since this was identified text message service as its main application. The key idea for SMS was to use this telephone-optimized system, and to transport messages on the signaling paths needed to control the telephone traffic during periods when no signaling traffic existed. In this way, unused text message service resources in the system could be used to transport messages at a minimal cost. However, it was necessary to limit the length of the messages to 128 bytes (later improved to 160 seven-bit characters) so that the messages could fit into the text message service existing signaling formats. Based on his personal observations and on analysis of the typical lengths of postcard and Telex messages, Hillebrand argued that 160 characters were sufficient to express most messages succinctly. Early Development The first proposal which initiated the development of text message service SMS was made by a contribution of Germany and France into the GSM group meeting in February 1985 in Oslo. This proposal was further elaborated in GSM subgroup WP1 Services (Chairman Martine Alvernhe, France Telecom) based on a contribution from Germany. There were also initial discussions in the subgroup WP3 network aspects chaired by Jan text message service Audestad (Telenor). The result was approved by the main GSM group in a June '85 document which was distributed to the industry. The input documents on SMS had been prepared by Friedhelm Hillebrand (Deutsche Telekom) with contributions text message service from Bernard Ghillebaert (France Télécom). The definition that Friedhelm Hillebrand and Bernard Ghillebaert text message service brought into GSM called for the provision of a message transmission service of alphanumeric messages to mobile users "with acknowledgment capabilities". 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. Early implementations The first SMS message was a text message service 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. The text of the text message service message was "Merry Christmas.