Short message service - AbsoluteAstronomy.com

Short Message Service (SMS) is a text messaging

Text messaging

Text messaging, or texting, refers to the exchange of brief written text messages between fixed-line phone or mobile phone and fixed or portable devices over a network...

service component of phone, web, or mobile communication systems, using standardized communications protocols that allow the exchange of short text messages between fixed line or mobile phone

Mobile phone

A mobile phone is a device which can make and receive telephone calls over a radio link whilst moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile network operator...

devices. SMS text messaging

Text messaging

Text messaging, or texting, refers to the exchange of brief written text messages between fixed-line phone or mobile phone and fixed or portable devices over a network...

is the most widely used data application in the world, with 2.4 billion active users, or 74% of all mobile phone subscribers. The term SMS is used as a synonym for all types of short text messaging as well as the user activity itself in many parts of the world. SMS is also being used as a form of direct marketing

Direct marketing

Direct marketing is a channel-agnostic form of advertising that allows businesses and nonprofits to communicate straight to the customer, with advertising techniques such as mobile messaging, email, interactive consumer websites, online display ads, fliers, catalog distribution, promotional...

known as SMS marketing

SMS marketing

SMS Marketing is a relatively new type of mobile marketing that uses SMS text messaging as a medium of direct advertising, often to a firms existing customers. An SMS Marketing campaign involves collecting mobile phone numbers usually by customer opt-ins using a keyword sent to a short code, which...

.
SMS as used on modern handsets was originated from radio telegraphy in radio memo pagers using standardized phone protocols and later defined as part of the Global System for Mobile Communications

Global System for Mobile Communications

GSM , is a standard set developed by the European Telecommunications Standards Institute to describe technologies for second generation digital cellular networks...

(GSM) series of standards in 1985 as a means of sending messages of up to 160 characters, to and from GSM mobile handsets. Since then, support for the service has expanded to include other mobile technologies such as ANSI CDMA networks

IS-95

Interim Standard 95 is the first CDMA-based digital cellular standard by Qualcomm. The brand name for IS-95 is cdmaOne. IS-95 is also known as TIA-EIA-95....

and Digital AMPS

Digital AMPS

IS-54 and IS-136 are second-generation mobile phone systems, known as Digital AMPS . It was once prevalent throughout the Americas, particularly in the United States and Canada. D-AMPS is considered end-of-life, and existing networks have mostly been replaced by GSM/GPRS or CDMA2000...

, as well as satellite and landline

Landline

A landline was originally an overland telegraph wire, as opposed to an undersea cable. Currently, landline refers to a telephone line which travels through a solid medium, either metal wire or optical fibre, as distinguished from a mobile cellular line, where transmission is via radio waves...

networks. Most SMS messages are mobile-to-mobile text messages though the standard supports other types of broadcast messaging as well.

Initial concept

The idea of adding text messaging to the services of mobile users was not frequent in many communities of mobile communication services at the beginning of the 1980s. The first action plan of the CEPT Group GSM, approved in December 1982, requested "The services and facilities offered in the public switched telephone networks and public data networks... should be available in the mobile system". This target includes the exchange of text messages either directly between mobile stations, or transmitted via Message Handling Systems widely in use since the beginning of the 1980s.

The SMS concept was developed in the Franco-German GSM cooperation in 1984 by Friedhelm Hillebrand and Bernard Ghillebaert. The innovation in SMS is Short. The GSM is optimized for telephony, since this was identified as its main application. The key idea for SMS was to use this telephony-optimized system, and to transport messages on the signaling paths needed to control the telephony 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 140 bytes, or 160 seven-bit characters) so that the messages could fit into the existing signaling formats.

This concept allowed SMS to be implemented in every mobile station by updating its software. This concept was instrumental for the implementation of SMS in every mobile station ever produced and in every network from early days. Hence, a large base of SMS capable terminals and networks existed when the users began to utilize the SMS. 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, and through these organizations the technology was made freely available to the whole world. This is described and supported by evidence in the following sections.

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. 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. The input documents on SMS had been prepared by Friedhelm Hillebrand (Deutsche Telekom

Deutsche Telekom

Deutsche Telekom AG is a telecommunications company headquartered in Bonn, Germany. It is the largest telecommunications company in Europe....

) with contributions from Bernard Ghillebaert (France Télécom

France Télécom

France Telecom S.A. is the main telecommunications company in France, the third-largest in Europe and one of the largest in the world. It currently employs about 180,000 people and has 192.7 million customers worldwide . In 2010 the group had revenue of €45.5 billion...

).

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", 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
Public land mobile network
A public land mobile network is a regulatory term in telecommunications. A PLMN is a network that is established and operated by an administration or by a recognized operating agency for the specific purpose of providing land mobile telecommunications services to the public.A PLMN is identified...

". 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
Cell Broadcast
Cell Broadcast messaging is a mobile technology feature defined by the ETSI’s GSM committee and is part of the GSM standard. It is also known as Short message service-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 together) 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 about five to eight participants, and Finn Trosby mentions as major contributors Kevin Holley, Eija Altonen, Didier Luizard and Alan Cox. The first action plan 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. 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.

The work on the draft specification continued in the following few years, where Kevin Holley of Cellnet (now Telefonica 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

Mobile Application Part

The Mobile Application Part is an SS7 protocol which provides an application layer for the various nodes in GSM and UMTS mobile core networks and GPRS core networks to communicate with each other in order to provide services to mobile phone users...

(MAP) of the SS7 protocol included support for the transport of Short Messages through the Core Network from its inception. MAP Phase 2 expanded support for SMS by introducing a separate operation code for Mobile Terminated Short Message transport. 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

3GPP

The 3rd Generation Partnership Project is a collaboration between groups of telecommunications associations, known as the Organizational Partners...

Releases 99 and 4 onwards, CAMEL

Customised Applications for Mobile networks Enhanced Logic

Customised Applications for Mobile networks Enhanced Logic, or CAMEL for short, is a set of standards designed to work on either a GSM core network or UMTS network. They allow an operator to define services over and above standard GSM services/UMTS services...

Phase 3 introduced the ability for the Intelligent Network (IN)

Intelligent network

The Intelligent Network , is the standard network architecture specified in the . It is intended for fixed as well as mobile telecom networks...

to control aspects of the Mobile Originated Short Message Service, while CAMEL Phase 4, as part of 3GPP Release 5 and onwards, provides the IN with the ability to control the Mobile Terminated service. CAMEL allows the gsmSCP

Service Control Point

A service control point is a standard component of the Intelligent Network telephone system which is used to control the service. Standard SCPs in the telecom industry today are deployed using SS7, Sigtran or SIP technologies. The SCP queries the service data point which holds the actual...

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)

INAP

The Intelligent Network Application Part is a signalling protocol used in the intelligent network architecture. It is part of the SS7 protocol suite, typically layered on top of TCAP.It can also be termed as logic for controlling telecommunication services migrated from traditional switching...

of SS7.

Early implementations

The first SMS message was sent over the Vodafone

Vodafone

Vodafone Group Plc is a global telecommunications company headquartered in London, United Kingdom. It is the world's largest mobile telecommunications company measured by revenues and the world's second-largest measured by subscribers , with around 341 million proportionate subscribers as of...

GSM network in the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

on 3 December 1992, from Neil Papworth of Sema Group

Sema Group

Sema Group plc was an Anglo-French IT services company. It was listed on the London Stock Exchange and was a constituent of the FTSE 100 Index but was acquired by Schlumberger in 2001.-History:...

(now Mavenir Systems

Airwide Solutions

Airwide Solutions was a privately held United States-based mobile messaging and wireless internet infrastructure company. It was acquired by Mavenir Systems in May 2011....

) using a personal computer to Richard Jarvis of Vodafone using an Orbitel

Orbitel

Orbitel is Bulgarian wireline telecommunications and Internet service provider with national licenses for voice and data. Through its national packet-switched network Orbitel provides convergent telecommunication solutions for telephony, high speed Internet and VPNs throughout Bulgaria...

901 handset. The text of the message was "Merry Christmas".

The first commercial deployment of a short message service center

Short message service center

A short message service center is a network element in the mobile telephone network which delivers SMS messages.-Operation:When a user sends a text message to another user, the message gets stored in the SMSC which delivers it to the destination user when they are available...

(SMSC) was by Aldiscon

Aldiscon

Aldiscon was a telecommunications software company founded in Dublin, Ireland in 1988. The company was an innovator in supplying software products to the mobile sector and became a market leader in the supply of Short Message Service Centre's to mobile operators globally.Aldiscon invented SMPP,...

part of Logica (now part of Acision

Acision

Acision is a privately held mobile communications network infrastructure company specialising in messaging and charging systems that enable popular services such as Short message service , Multimedia Messaging Service , mobile internet browsing, Mobile Broadband and voicemail.-History:Acision's...

) with Telia (now TeliaSonera

TeliaSonera

TeliaSonera AB is the dominant telephone company and mobile network operator in Sweden and Finland. The company has operations in other countries in Northern, Eastern Europe, Central Asia and Spain, with a total of 150 million mobile customers...

) in Sweden in 1993, followed by Fleet Call (now Nextel) in the US, Telenor in Norway and BT Cellnet (now O2 UK) 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. 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

Short message service center

settings on individual handsets to use the SMSCs of other operators.

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, and by Christmas Day 2006, over 205 million messages were sent in the UK alone.

It is also alleged that the fact that roaming customers, in the early days, rarely received bills for their SMSs after holidays abroad had a boost on text messaging as an alternative to voice calls.

Text messaging outside GSM

SMS was originally designed as part of GSM, but is now available on a wide range of networks, including 3G

3G or 3rd generation mobile telecommunications is a generation of standards for mobile phones and mobile telecommunication services fulfilling the International Mobile Telecommunications-2000 specifications by the International Telecommunication Union...

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

NTT DoCoMo

is the predominant mobile phone operator in Japan. The name is officially an abbreviation of the phrase, "do communications over the mobile network", and is also from a compound word dokomo, meaning "everywhere" in Japanese. Docomo provides phone, video phone , i-mode , and mail services...

's Short Mail, both in Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. Email messaging from phones, as popularized by NTT Docomo's i-mode

I-mode

NTT DoCoMo's i-mode is a mobile internet service popular in Japan. Unlike Wireless Application Protocol, i-mode encompasses a wider variety of internet standards, including web access, e-mail and the packet-switched network that delivers the data...

and the RIM

Research In Motion

Research In Motion Limited or RIM is a Canadian multinational telecommunications company headquartered in Waterloo, Ontario, Canada that designs, manufactures and markets wireless solutions for the worldwide mobile communications market...

BlackBerry

BlackBerry is a line of mobile email and smartphone devices developed and designed by Canadian company Research In Motion since 1999.BlackBerry devices are smartphones, designed to function as personal digital assistants, portable media players, internet browsers, gaming devices, and much more...

, also typically uses standard mail protocols such as SMTP

Simple Mail Transfer Protocol

Simple Mail Transfer Protocol is an Internet standard for electronic mail transmission across Internet Protocol networks. SMTP was first defined by RFC 821 , and last updated by RFC 5321 which includes the extended SMTP additions, and is the protocol in widespread use today...

over TCP/IP

Internet protocol suite

The Internet protocol suite is the set of communications protocols used for the Internet and other similar networks. It is commonly known as TCP/IP from its most important protocols: Transmission Control Protocol and Internet Protocol , which were the first networking protocols defined in this...

SMS today

In 2010, 6.1 trillion SMS text messages were sent. This translates into 192000 SMS per second. SMS has become a massive commercial industry, worth over $81 billion globally as of 2006. 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.

While SMS is still a growing market, traditional SMS are becoming increasingly challenged by alternative messaging services which are available on smartphones with data connections, especially in western countries some of these services attract users.

GSM

The Short Message Service – Point to Point (SMS-PP) was originally defined in GSM recommendation 03.40, which is now maintained in 3GPP

3GPP

The 3rd Generation Partnership Project is a collaboration between groups of telecommunications associations, known as the Organizational Partners...

as TS 23.040. 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.

Messages are sent to a Short message service center

Short message service center

(SMSC) which provides a "store and forward

Store and forward

Store and forward is a telecommunications technique in which information is sent to an intermediate station where it is kept and sent at a later time to the final destination or to another intermediate station. The intermediate station, or node in a networking context, verifies the integrity of...

" 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. 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

Best effort delivery

Best effort delivery describes a network service in which the network does not provide any guarantees that data is delivered or that a user is given a guaranteed quality of service level or a certain priority...

", 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% of messages. 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.

Message size

Transmission of short messages between the SMSC and the handset is done whenever using the Mobile Application Part

Mobile Application Part

(MAP) of the SS7 protocol. 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

Octet (computing)

An octet is a unit of digital information in computing and telecommunications that consists of eight bits. The term is often used when the term byte might be ambiguous, as there is no standard for the size of the byte.-Overview:...

(140 octets = 140 * 8 bits = 1120 bits). Short messages can be encoded using a variety of alphabets: the default GSM 7-bit alphabet

GSM 03.38

In Mobile telephony GSM 03.38 is a character set used in the Short Message Service of GSM based cell phones. It is defined in GSM recommendation 03.38. Messages sent via this encoding can be encoded in the default GSM 7-bit alphabet, the 8-bit data alphabet, and the 16-bit UTF-16 alphabet...

, the 8-bit

Bit

A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...

data alphabet, and the 16-bit UTF-16 alphabet. Depending on which alphabet the subscriber has configured in the handset, this leads to the maximum individual short message sizes of 160 7-bit

Bit

characters, 140 8-bit characters, or 70 16-bit characters (including spaces). GSM 7-bit alphabet support is mandatory for GSM handsets and network elements, 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 UTF-16 character encoding

Character encoding

A character encoding system consists of a code that pairs each character from a given repertoire with something else, such as a sequence of natural numbers, octets or electrical pulses, in order to facilitate the transmission of data through telecommunication networks or storage of text in...

(see Unicode

Unicode

Unicode is a computing industry standard for the consistent encoding, representation and handling of text expressed in most of the world's writing systems...

). Routing

Routing

Routing is the process of selecting paths in a network along which to send network traffic. Routing is performed for many kinds of networks, including the telephone network , electronic data networks , and transportation networks...

data and other metadata

Metadata

The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...

is additional to the payload size.

Larger content (concatenated SMS

Concatenated SMS

In the cellular phone industry, mobile phones and their networks sometimes support concatenated short message service to overcome the limitation on the number of characters that can be sent in a single SMS text message transmission...

, 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, 6 to 8 segment messages are the practical maximum, and long messages are often billed as equivalent to multiple SMS messages. See concatenated SMS

Concatenated SMS

for more information. Some providers have offered length-oriented pricing schemes for messages, however, the phenomenon is disappearing.

SMS Gateway providers

SMS gateway providers facilitate SMS traffic between businesses and mobile subscribers, including mission-critical messages, SMS for enterprises, content delivery, and entertainment services involving SMS, e.g. TV voting. Considering SMS messaging performance and cost, as well as the level of messaging services, SMS gateway providers can be classified as aggregators or SS7 providers.

The aggregator model is based on multiple agreements with mobile carriers to exchange two-way SMS traffic into and out of the operator's SMSC

Short message service center

, also known as local termination model. Aggregators lack direct access into the SS7 protocol, which is the protocol where the SMS messages are exchanged. SMS messages are delivered to the operator's SMSC, but not the subscriber's handset; the SMSC takes care of further handling of the message through the SS7 network.

Another type of SMS gateway provider is based on SS7 connectivity to route SMS messages, also known as international termination model. The advantage of this model is the ability to route data directly through SS7, which gives the provider total control and visibility of the complete path during SMS routing. This means SMS messages can be sent directly to and from recipients without having to go through the SMSCs of other mobile operators. Therefore, it is possible to avoid delays and message losses, offering full delivery guarantees of messages and optimized routing. This model is particularly efficient when used in mission-critical messaging and SMS used in corporate communications.

Interconnectivity with other networks

Message Service Centers communicate with the Public Land Mobile Network (PLMN)

Public land mobile network

A public land mobile network is a regulatory term in telecommunications. A PLMN is a network that is established and operated by an administration or by a recognized operating agency for the specific purpose of providing land mobile telecommunications services to the public.A PLMN is identified...

or PSTN

Public switched telephone network

The public switched telephone network is the network of the world's public circuit-switched telephone networks. It consists of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all inter-connected by...

via Interworking and Gateway MSCs.

Subscriber-originated messages are transported from a handset to a Service Center, and may be destined for mobile users, subscribers on a fixed network, or Value-Added Service Providers (VASPs)

Value-added service

A value-added service is popular as a telecommunications industry term for non-core services, or in short, all services beyond standard voice calls and fax transmissions. However, it can be used in any service industry, for services available at little or no cost, to promote their primary business...

, also known as application-terminated. Subscriber-terminated messages are transported from the Service Center to the destination handset, and may originate from mobile users, from fixed network subscribers, or from other sources such as VASPs.

On some carriers non-subscribers can send messages to a subscriber's phone using an Email-to-SMS gateway. Additionally, many carriers, including AT&T

AT&T

AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...

, T-Mobile USA

T-Mobile USA

T-Mobile USA, Inc. is an American mobile-network operator, headquartered in Bellevue, Washington, that provides wireless voice, messaging and data services in the United States, Puerto Rico and the U.S. Virgin Islands. The company is the fourth-largest wireless carrier in the U.S. market with 33.73...

, Sprint

Sprint Nextel

Sprint Nextel Corporation is an American telecommunications company based in Overland Park, Kansas. The company owns and operates Sprint, the third largest wireless telecommunications network in the United States, with 53.4 million customers, behind Verizon Wireless and AT&T Mobility...

, and Verizon Wireless

Verizon Wireless

Cellco Partnership, doing business as Verizon Wireless, is one of the largest mobile network operators in the United States. The network has 107.7 million subscribers as of 2011, making it the largest wireless service provider in America....

, offer the ability to do this through their respective websites.

For example, an AT&T subscriber whose phone number was 555-555-5555 would receive e-mails addressed to 5555555555@txt.att.net as text messages. AT&T subscribers can easily reply to these SMS messages, and the SMS reply is sent back to the original email address. Sending email to SMS is free for the sender, but the recipient is subject to the standard delivery charges. Only the first 160 characters of an email message can be delivered to a phone, and only 160 characters can be sent from a phone.

Text-enabled fixed-line handsets are required to receive messages in text format. However, messages can be delivered to non-enabled phones using text-to-speech conversion

Speech synthesis

Speech synthesis is the artificial production of human speech. A computer system used for this purpose is called a speech synthesizer, and can be implemented in software or hardware...

.

Short messages can send binary content such as ringtones or logos, as well as Over-the-air programming

Over-the-air programming

Over-the-air programming refers to various methods of distributing new software updates or configuration settings to devices like cellphones and set-top boxes...

(OTA) or configuration data. Such uses are a vendor-specific extension of the GSM specification and there are multiple competing standards, although Nokia

Nokia

Nokia Corporation is a Finnish multinational communications corporation that is headquartered in Keilaniemi, Espoo, a city neighbouring Finland's capital Helsinki...

's Smart Messaging

Smart message

Smart message is a protocol designed by Intel and Nokia, and by which various software upgrades— including ringtones — can be made "over the air", through the wireless connection....

is common. An alternative way for sending such binary content is EMS

Enhanced Messaging Service

Enhanced Messaging Service , is a cross-industry collaboration between Samsung, Ericsson, Motorola, Siemens and Alcatel, among others. It is an application-level extension to Short Message Service for cellular phones available on GSM, TDMA and CDMA networks.EMS is an intermediate technology,...

messaging, which is standardized and not dependent on vendors.

SMS is used for M2M (Machine to Machine

Machine to Machine

Machine-to-Machine refers to technologies that allow both wireless and wired systems to communicate with other devices of the same ability...

) communication. For instance, there is an LED display machine controlled by SMS, and some vehicle tracking

Vehicle tracking system

A vehicle tracking system combines the installation of an electronic device in a vehicle, or fleet of vehicles, with purpose-designed computer software at least at one operational base to enable the owner or a third party to track the vehicle's location, collecting data in the process from the...

companies use SMS for their data transport

Transport

Transport or transportation is the movement of people, cattle, animals and goods from one location to another. Modes of transport include air, rail, road, water, cable, pipeline, and space. The field can be divided into infrastructure, vehicles, and operations...

or telemetry

Telemetry

Telemetry is a technology that allows measurements to be made at a distance, usually via radio wave transmission and reception of the information. The word is derived from Greek roots: tele = remote, and metron = measure...

needs. SMS usage for these purposes is slowly being superseded by GPRS

General Packet Radio Service

General packet radio service is a packet oriented mobile data service on the 2G and 3G cellular communication system's global system for mobile communications . GPRS was originally standardized by European Telecommunications Standards Institute in response to the earlier CDPD and i-mode...

services due to their lower overall cost. GPRS is offered by smaller telco players as a route of sending SMS text to reduce the cost of SMS texting internationally.

AT commands

Many mobile and satellite transceiver

Transceiver

A transceiver is a device comprising both a transmitter and a receiver which are combined and share common circuitry or a single housing. When no circuitry is common between transmit and receive functions, the device is a transmitter-receiver. The term originated in the early 1920s...

units support the sending and receiving of SMS using an extended version of the Hayes command set

Hayes command set

The Hayes command set is a specific command-language originally developed for the Hayes Smartmodem 300 baud modem in 1981. The command set consists of a series of short text strings which combine together to produce complete commands for operations such as dialing, hanging up, and changing the...

, a specific command language

Command language

A command language is a domain-specific interpreted language; a common example of a command language are shell or batch programming languages. These languages can be used directly at the command line, but can also automate tasks that would normally be performed manually at the command line...

originally developed for the Hayes

Hayes Microcomputer Products

Hayes Microcomputer Products was a U.S.-based manufacturer of modems. They are particularly well known for their Smartmodem, which is introduced the ability to control the modem through commands sent in the data stream itself. The "smart modem" approach dramatically simplified operation, making...

Smartmodem 300-baud

Baud

In telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a...

modem in 1977.

The connection between the terminal equipment and the transceiver can be realized with a serial cable (e.g. USB), a Bluetooth

Bluetooth

Bluetooth is a proprietary open wireless technology standard for exchanging data over short distances from fixed and mobile devices, creating personal area networks with high levels of security...

link, an infrared

Infrared

Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...

link, etc. Common AT commands include AT+CMGS (send message), AT+CMSS (send message from storage), AT+CMGL (list messages) and AT+CMGR (read message).

However, not all modern devices support receiving of messages if the message storage (for instance the device's internal memory) is not accessible using AT commands.

Premium-rated short messages

Short messages may be used to provide premium rate services to subscribers of a telephone network.

Mobile-terminated short messages can be used to deliver digital content such as news alerts, financial information, logos and ring tones. The first premium-rate media content delivered via the SMS system was the world's first paid downloadable ringing tones, as commercially launched by Saunalahti (later Jippii Group, now part of Elisa Group) in 1998. Initially only Nokia branded phones could handle them. By 2002 the ringtone business globally had exceeded one billion US dollars of service revenues, and nearly 5 billion dollars by 2008. Today, they are also used to pay smaller payments online, for example for file sharing services, in mobile application stores or VIP section entrance. Outside the online world, one can buy a bus ticket, bevarages from ATM, pay parking ticket, order a store catalog or some goods (e.g. discount movie DVDs) and many more.

Premium-rated messages are also used in Donors Message Service

Donors Message Service

Donors Message Service is a mutual project of the Czech Donors Forum and the Association of Cellular Networks Operators launched on April 1, 2004. The aim of the DMS project is to offer foundations and other non-profit organizations the opportunity to obtain contributions from individuals via...

to collect money for charities and foundations. DMS was first launched at April 1, 2004 and is very popular in the Czech Republic

Czech Republic

The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....

, e.g. the Czech people sent over 1.5 million messages to help South Asia recover from 2004 Indian Ocean Earthquake

2004 Indian Ocean earthquake

The 2004 Indian Ocean earthquake was an undersea megathrust earthquake that occurred at 00:58:53 UTC on Sunday, December 26, 2004, with an epicentre off the west coast of Sumatra, Indonesia. The quake itself is known by the scientific community as the Sumatra-Andaman earthquake...

.

The Value-added service provider (VASP) providing the content submits the message to the mobile operator's SMSC(s) using a TCP/IP

Internet protocol suite

protocol such as the short message peer-to-peer protocol

Short message peer-to-peer protocol

The Short Message Peer-to-Peer protocol is a telecommunications industry protocol for exchanging SMS messages between SMS peer entities such as short message service centers and/or External Short Messaging Entities. It is often used to allow third parties The Short Message Peer-to-Peer (SMPP)...

(SMPP) or the External Machine Interface (EMI)

EMI (protocol)

External Machine Interface , an extension to Universal Computer Protocol , is a protocol primarily used to connect to short message service centres for mobile telephones...

. The SMSC delivers the text using the normal Mobile Terminated delivery procedure. The subscribers are charged extra for receiving this premium content; the revenue is typically divided between the mobile network operator

Mobile network operator

A mobile network operator , also known as mobile phone operator , carrier service provider , wireless service provider, wireless carrier, or cellular company, or mobile network carrier is a telephone company that provides services for mobile phone subscribers.One essential...

and the VASP either through revenue share or a fixed transport fee. Submission to the SMSC is usually handled by a third party.

Mobile-originated short messages may also be used in a premium-rated manner for services such as televoting

Televoting

Televoting, telephone voting or phone voting is a method of decision making and opinion polling conducted by telephone. Televoting can also extend to voting by SMS text message via a mobile cell phone.- Broadcast contest televoting :...

. In this case, the VASP providing the service obtains a short code

Short code

Short codes are special telephone numbers, significantly shorter than full telephone numbers, that can be used to address SMS and MMS messages from certain service provider's mobile phones or fixed phones...

from the telephone network operator, and subscribers send texts to that number. The payouts to the carriers vary by carrier; percentages paid are greatest on the lowest-priced premium SMS services. Most information providers should expect to pay about 45% of the cost of the premium SMS up front to the carrier. The submission of the text to the SMSC is identical to a standard MO Short Message submission, but once the text is at the SMSC, the Service Center (SC) identifies the Short Code as a premium service. The SC will then direct the content of the text message to the VASP, typically using an IP

Internet protocol suite

protocol such as SMPP or EMI. Subscribers are charged a premium for the sending of such messages, with the revenue typically shared between the network operator and the VASP. Short codes only work within one country, they are not international.

An alternative to inbound SMS is based on long numbers

Long numbers

Long number, also known as a virtual mobile number, dedicated phone number or long code, is a reception mechanism used by businesses to receive SMS messages and voice calls...

(international number format, e.g. +44 762 480 5000), which can be used in place of short codes for SMS reception in several applications, such as TV voting, product promotions and campaigns. Long numbers work internationally, allow businesses to use their own numbers, rather than short codes which are usually shared across a lot of brands. Additionally, long numbers are non-premium inbound numbers.

SMS in satellite phone networks

All commercial satellite phone

Satellite phone

A satellite telephone, satellite phone, or satphone is a type of mobile phone that connects to orbiting satellites instead of terrestrial cell sites...

networks except ACeS

ACeS

ACeS is a regional satellite telecommunications company based in Jakarta, Indonesia. It offers GSM-like satellite telephony services to Asian market. The coverage area includes Indonesia, Malaysia, Thailand, Philippines, Sri Lanka, Vietnam, China and India. The company operates the Garuda 1...

and OptusSat

Optus fleet of satellites

This is a list of the satellites operated by Optus, an Australian telecommunications company. The satellite communications facility is located at Belrose on Sydney’s Northern Beaches.-A-Class:*Satellite Type: Hughes HS-376...

support SMS. While early Iridium handsets only support incoming SMS, later models can also send messages. The price per message varies for different networks. Unlike some mobile phone networks, there is no extra charge for sending international SMS or to send one to a different satellite phone network. SMS can sometimes be sent from areas where the signal is too poor to make a voice call.

Satellite phone networks usually have web-based or email-based SMS portals where one can send free SMS to phones on that particular network. Other commercial service providers such as Targlets allow for SMS on the +881 and +882 numbering plan prefix. Some other providers also cover the +870 plan.

Unreliability

Unlike dedicated texting systems like the Simple Network Paging Protocol

Simple Network Paging Protocol

Simple Network Paging Protocol is a protocol that defines a method by which a pager can receive a message over the Internet. It is supported by most major paging providers, and serves as an alternative to the paging modems used by many telecommunications services. The protocol was most recently...

and Motorola's ReFLEX protocol, SMS message delivery is not guaranteed, and many implementations provide no mechanism through which a sender can determine whether an SMS message has been delivered in a timely manner. SMS messages are generally treated as lower-priority traffic than voice, and various studies have shown that around 1% to 5% of messages are lost entirely, even during normal operation conditions, and others may not be delivered until long after their relevance has passed. The use of SMS as an emergency notification service in particular has been starkly criticized.

Vulnerabilities

The Global Service for Mobile communications (GSM), with the greatest worldwide number of users, succumbs to several security vulnerabilities. In the GSM, only the airway traffic between the Mobile Station

Mobile Station

The mobile station comprises all user equipment and software needed for communication with a mobile network.The mobile station refers to global system connected to the mobile network, i.e. mobile phone or mobile computer connected using a mobile broadband adapter. This is the terminology of 2G...

(MS) and the Base Transceiver Station

Base Transceiver Station

A base transceiver station or cell site is a piece of equipment that facilitates wireless communication between user equipment and a network. UEs are devices like mobile phones , WLL phones, computers with wireless internet connectivity, WiFi and WiMAX gadgets etc...

(BTS) is optionally encrypted with a weak and broken stream cipher

Stream cipher

In cryptography, a stream cipher is a symmetric key cipher where plaintext digits are combined with a pseudorandom cipher digit stream . In a stream cipher the plaintext digits are encrypted one at a time, and the transformation of successive digits varies during the encryption...

(A5/1

A5/1

A5/1 is a stream cipher used to provide over-the-air communication privacy in the GSM cellular telephone standard. It was initially kept secret, but became public knowledge through leaks and reverse engineering. A number of serious weaknesses in the cipher have been identified.-History and...

or A5/2

A5/2

A5/2 is a stream cipher used to provide voice privacy in the GSM cellular telephone protocol.The cipher is based around a combination of four linear feedback shift registers with irregular clocking and a non-linear combiner.In 1999, Ian Goldberg and David A...

). The authentication

Authentication

Authentication is the act of confirming the truth of an attribute of a datum or entity...

is unilateral and also vulnerable. There are also many other security vulnerabilities and shortcomings. Such vulnerabilities are inherent to SMS

Short message service

Short Message Service is a text messaging service component of phone, web, or mobile communication systems, using standardized communications protocols that allow the exchange of short text messages between fixed line or mobile phone devices...

as one of the superior and well-tried services with a global availability in the GSM networks. SMS messaging has some extra security vulnerabilities due to its store-and-forward feature, and the problem of fake SMS that can be conducted via the Internet. When a user is roaming, SMS content passes through different networks, perhaps including the Internet, and is exposed to various vulnerabilities and attacks. Another concern arises when an adversary gets access to a phone and reads the previous unprotected messages.

In October 2005, researchers from Pennsylvania State University

Pennsylvania State University

The Pennsylvania State University, commonly referred to as Penn State or PSU, is a public research university with campuses and facilities throughout the state of Pennsylvania, United States. Founded in 1855, the university has a threefold mission of teaching, research, and public service...

published an analysis of vulnerabilities in SMS-capable cellular networks. The researchers speculated that attackers might exploit the open functionality of these networks to disrupt them or cause them to fail, possibly on a nationwide scale.

SMS spoofing

The GSM industry has identified a number of potential fraud attacks on mobile operators that can be delivered via abuse of SMS messaging services. The most serious of threats is SMS Spoofing. SMS Spoofing occurs when a fraudster manipulates address information in order to impersonate a user that has roamed onto a foreign network and is submitting messages to the home network. Frequently, these messages are addressed to destinations outside the home network – with the home SMSC essentially being “hijacked” to send messages into other networks.

The only sure way of detecting and blocking spoofed messages is to screen incoming mobile-originated messages to verify that the sender is a valid subscriber and that the message is coming from a valid and correct location. This can be implemented by adding an intelligent routing function to the network that can query originating subscriber details from the HLR before the message is submitted for delivery. This kind of intelligent routing function is beyond the capabilities of legacy messaging infrastructure.

SMS limitation

In an effort to limit telemarketers, who had taken to bombarding users with hordes of unsolicited messages, India introduced new regulations in September of 2011, including a cap of 3,000 SMS messages per subscriber per month, or an average of 100 per subscriber per day.
Due to representations received from some of the service providers and consumers, TRAI (Telecom Regulatory Authority of India) has raised this limit to 200 SMS messages per sim per day in case of prepaid

Prepaid

Prepaid refers to services paid for in advance. Examples include postage stamps, tolls, transit cards like the Greater London Oyster card, pay as you go cell phones, and stored-value cards such as gift cards and preloaded credit cards like American Express...

services, and upto 6,000 SMS messages per sim per month in case of postpaid

Postpaid

Post Paid: A model of cellular service whereby the customer is charged for usage in the prior month , and hence does not feature any limitations on volume of service used...

services with effect from 1st November 2011.

Flash SMS

A Flash SMS is a type of SMS that appears directly on the main screen without user interaction and is not automatically stored in the inbox. It can be useful in cases such as an emergency

Emergency

An emergency is a situation that poses an immediate risk to health, life, property or environment. Most emergencies require urgent intervention to prevent a worsening of the situation, although in some situations, mitigation may not be possible and agencies may only be able to offer palliative...

(e.g. fire alarm

Fire alarm system

An automatic fire alarm system is designed to detect the unwanted presence of fire by monitoring environmental changes associated with combustion. In general, a fire alarm system is classified as either automatically actuated, manually actuated, or both...

) or confidentiality

Confidentiality

Confidentiality is an ethical principle associated with several professions . In ethics, and in law and alternative forms of legal resolution such as mediation, some types of communication between a person and one of these professionals are "privileged" and may not be discussed or divulged to...

(e.g. one-time password

One-time password

A one-time password is a password that is valid for only one login session or transaction. OTPs avoid a number of shortcomings that are associated with traditional passwords. The most important shortcoming that is addressed by OTPs is that, in contrast to static passwords, they are not vulnerable...

Emergency Services

In some countries SMS messages can be used to contact the emergency services. In the United Kingdom

United Kingdom

, SMS text messages can be used to contact the local emergency services provider after registering with the emergency SMS service. This service is primarily aimed at people who by reason of disability are unable to make a voice call but has recently been promoted as a means for walkers and climbers to call emergency services from areas where a voice call is not possible due to low signal strength. Such service is also available in Hong Kong

Hong Kong

Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...

External links

3GPP – The organization that maintains the SMS specification.
SMS, the strange duckling of GSM
ISO Standards (In Zip file format)
GSM 03.38 to Unicode – the official GSM
SMS FAQs (GSM-Technology.com) – includes definitions of Class 0, Class 1, Class 2 and Class 3 MT (Mobile Terminated) messages
SMS PDU mode (PDU = Protocol Description Unit)

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

Initial concept

Early development

Support in other architectures

Early implementations

Text messaging outside GSM

SMS today

GSM

Message size

SMS Gateway providers

Interconnectivity with other networks

AT commands

Premium-rated short messages

SMS in satellite phone networks

Unreliability

Vulnerabilities

SMS spoofing

SMS limitation

Flash SMS

Emergency Services

See also

External links