Sms Service Biography
source(google.com.pk)Short Message Service (SMS) is a text messaging service component of phone, web, or mobile communication systems. It uses standardized communications protocols to allow fixed line or mobile phone devices to exchange short text messages.[1]
SMS is the most widely used data application, with an estimated 3.5 billion active users, or about 80% of all mobile phone subscribers at the end of 2010.[2] The term "SMS" is used for all types of short text messaging and the user activity itself in many parts of the world. SMS is also employed in direct marketing, known as SMS marketing.[3]
SMS as used on modern handsets originated from radio telegraphy in radio memo pagers using standardized phone protocols. These were defined in 1985 as part of the Global System for Mobile Communications (GSM) series of standards[4] as a means of sending messages of up to 160 characters[5][6] to and from GSM mobile handsets.[7] Though 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, as well as satellite and landline networks.[citation needed]Initial concept
SMS messages sent monthly in USA (billion)
Adding text messaging functionality to mobile devices began in the early 1980s. The first action plan of the CEPT Group GSM was approved in December 1982, requesting "The services and facilities offered in the public switched telephone networks and public data networks... should be available in the mobile system".[8] This plan included the exchange of text messages either directly between mobile stations, or transmitted via Message Handling Systems widely in use at that time.[9]
The SMS concept was developed in the Franco-German GSM cooperation in 1984 by Friedhelm Hillebrand and Bernard Ghillebaert.[10] The GSM is optimized for telephony, since this was identified 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 time periods when no signaling traffic existed. In this way, unused resources in the system could be used to transport messages at 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 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 was sufficient to express most messages succinctly.[5]
SMS could be implemented in every mobile station by updating its software. Hence, a large base of SMS capable terminals and networks existed when people began to use SMS.[11] A new network element required was a specialized short message service center, and enhancements were required to the radio capacity and network transport infrastructure to accommodate growing SMS traffic.
Early development
The technical development of SMS was a multinational collaboration supporting the framework of standards bodies. Through these organizations the technology was made freely available to the whole world.[12]
The first proposal which initiated the development of SMS was made by a contribution of Germany and France into the GSM group meeting in February 1985 in Oslo.[13] 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 Audestad (Telenor). The result was approved by the main GSM group in a June '85 document which was distributed to industry.[14] The input documents on SMS had been prepared by Friedhelm Hillebrand (Deutsche Telekom) with contributions from Bernard Ghillebaert (France Télécom). The definition that Friedhelm Hillebrand and Bernard Ghillebaert brought into GSM called for the provision of a message transmission service of alphanumeric messages to mobile users "with acknowledgement 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.[15]
SMS was considered in the main GSM group as a possible service for the new digital cellular system. In GSM document “Services and Facilities to be provided in the GSM System,”[4] both mobile-originated and mobile-terminated short messages appear on the table of GSM teleservices.
The discussions on the GSM services were concluded in the recommendation GSM 02.03 “TeleServices supported by a GSM PLMN.”[16] Here a rudimentary description of the three services was given:
Short message Mobile Terminated (SMS-MT)/ Point-to-Point: the ability of a network to transmit a Short Message to a mobile phone. The message can be sent by phone or by a software application.
Short message Mobile Originated (SMS-MO)/ Point-to-Point: the ability of a network to transmit a Short Message sent by a mobile phone. The message can be sent to a phone or to a software application.
Short message Cell Broadcast.
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). The technical standard known today was largely created by IDEG (later WP4) as the two recommendations GSM 03.40 (the two point-to-point services merged) and GSM 03.41 (cell broadcast).
WP4 created a Drafting Group Message Handling (DGMH), which was responsible for the specification of SMS. 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 first action plan[17] mentions for the first time the Technical Specification 03.40 “Technical Realisation of the Short Message Service”. Responsible editor was Finn Trosby. The first and very rudimentary draft of the technical specification was completed in November 1987.[18] However, drafts useful for the manufacturers followed at a later stage in the period. A comprehensive description of the work in this period is given in.[19]
The work on the draft specification continued in the following few years, where Kevin Holley of Cellnet (now Telefónica O2 UK) played a leading role. Besides the completion of the main specification GSM 03.40, the detailed protocol specifications on the system interfaces also needed to be completed.
Support in other architectures
The Mobile Application Part (MAP) of the SS7 protocol included support for the transport of Short Messages through the Core Network from its inception.[20] MAP Phase 2 expanded support for SMS by introducing a separate operation code for Mobile Terminated Short Message transport.[21] Since Phase 2, there have been no changes to the Short Message operation packages in MAP, although other operation packages have been enhanced to support CAMEL SMS control.
From 3GPP Releases 99 and 4 onwards, CAMEL Phase 3 introduced the ability for the Intelligent Network (IN) to control aspects of the Mobile Originated Short Message Service,[22] while CAMEL Phase 4, as part of 3GPP Release 5 and onwards, provides the IN with the ability to control the Mobile Terminated service.[23] CAMEL allows the gsmSCP 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. 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.
Early implementations
The first SMS message[24] 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. The text of the message was “Merry Christmas.”[25]
The first commercial deployment of a short message service center (SMSC) was by Aldiscon part of Logica (now part of Acision) with Telia (now TeliaSonera) in Sweden in 1993,[26] followed by Fleet Call (now Nextel)[27] in the US, Telenor in Norway[citation needed] and BT Cellnet (now O2 UK)[citation needed] later in 1993. All first installations of SMS gateways were for network notifications sent to mobile phones, usually to inform of voice mail messages. The first commercially sold SMS service was offered to consumers, as a person-to-person text messaging service by Radiolinja (now part of Elisa) in Finland in 1993. Most early GSM mobile phone handsets did not support the ability to send SMS text messages, and Nokia was the only handset manufacturer whose total GSM phone line in 1993 supported user-sending of SMS text messages.
Initial growth was slow, with customers in 1995 sending on average only 0.4 messages per GSM customer per month.[28] One factor in the slow takeup of SMS was that operators were slow to set up charging systems, especially for prepaid subscribers, and eliminate billing fraud which was possible by changing SMSC settings on individual handsets to use the SMSCs of other operators.[citation needed] Initially, networks in the UK only allowed customers to send messages to other users on the same network, limiting the usefulness of the service. This restriction was lifted in 1999.[24]
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,[28] and by Christmas Day 2006, over 205 million messages were sent in the UK alone.[29]
It is also alleged that the fact that roaming customers, in the early days, rarely received bills for their SMSs after holidays abroad which gave a boost to text messaging as an alternative to voice calls.[citation needed]
Text messaging outside GSM
SMS was originally designed as part of GSM, but is now available on a wide range of networks, including 3G networks. However, not all text messaging systems use SMS, and some notable alternative implementations of the concept include J-Phone's SkyMail and NTT Docomo's Short Mail, both in Japan. Email messaging from phones, as popularized by NTT Docomo's i-mode and the RIM BlackBerry, also typically uses standard mail protocols such as SMTP over TCP/IP.
SMS today
In 2010, 6.1 trillion SMS text messages were sent.[30] This translates into 193000 SMS per second.[31] SMS has become a massive commercial industry, earning $114.6 billion globally in 2010.[32] The global average price for an SMS message is $0.11, while mobile networks charge each other interconnect fees of at least $0.04 when connecting between different phone networks.[citation needed]
While SMS is still a growing market, traditional SMS are becoming increasingly challenged by alternative messaging services available on smartphones with data connections, especially in Western countries where these services are growing in popularity.[33]
Technical details
GSM
Main article: 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.[7][34] 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.[35][36]
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.[37] 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.[38] Some providers allow users to request delivery reports, either via the SMS settings of most modern phones, or by prefixing each message with *0# or *N#. However, the exact meaning of confirmations varies from reaching the network, to being queued for sending, to being sent, to receiving a confirmation of receipt from the target device, and users are often not informed of the specific type of success being reported.
SMS is a stateless communication protocol in which every SMS message is considered entirely independent of other messages. Enterprise applications using SMS as a data bearer require that session management be maintained external to the protocol.
Message size
Transmission of short messages between the SMSC and the handset is done whenever using the Mobile Application Part (MAP) of the SS7 protocol.[39] Messages are sent with the MAP MO- and MT-ForwardSM operations, whose payload length is limited by the constraints of the signaling protocol to precisely 140 octets (140 octets = 140 * 8 bits = 1120 bits). Short messages can be encoded using a variety of alphabets: the default GSM 7-bit alphabet, the 8-bit data alphabet, and the 16-bit UCS-2 alphabet.[40] Depending on which alphabet the subscriber has configured in the handset, this leads to the maximum individual short message sizes of 160 7-bit characters, 140 8-bit characters, or 70 16-bit characters. GSM 7-bit alphabet support is mandatory for GSM handsets and network elements,[40] but characters in languages such as Arabic, Chinese, Korean, Japanese, or Cyrillic alphabet languages (e.g., Russian, Serbian, Bulgarian, etc.) must be encoded using the 16-bit UCS-2 character encoding (see Unicode). Routing data and other metadata is additional to the payload size.
Larger content (concatenated SMS, multipart or segmented SMS, or "long SMS") can be sent using multiple messages, in which case each message will start with a User Data Header (UDH) containing segmentation information. Since UDH is part of the payload, the number of available characters per segment is lower: 153 for 7-bit encoding, 134 for 8-bit encoding and 67 for 16-bit encoding. The receiving handset is then responsible for reassembling the message and presenting it to the user as one long message. While the standard theoretically permits up to 255 segments,[41] 6 to 8 segment messages are the practical maximum, and long messages are often billed as equivalent to multiple SMS messages. Some providers have offered length-oriented pricing schemes for messages, however, the phenomenon is disappearing.
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