What is SMS?

“txtin iz messin,
mi headn’me englis,
try2rite essays,
they all come out txtis.
gran not plsed w/letters shes getn,
swears i wrote better
b4 comin2uni.
&she’s African”

- Hetty, who in 2001 received £1,000 first prize from
The Guardian in SMS poetry competition

What is SMS?

Short Message Service (SMS) is a communications protocol allowing the interchange of short text messages between mobile telephone devices. The SMS technology has facilitated the development and growth of text messaging. The connection between the phenomenon of text messaging and the underlying technology is so great that in parts of the world the term “SMS” is used colloquially as a synonym for a text message from another person or the act of sending a text message.

To put it simple, SMS is a system (and often the text message itself) for sending and receiving text messages by mobile phone. It is often called “texting” or TXT in the US.

Technical Information

The SMS technology is supported by leading cellular networks – GSM and CDMA. Also, SMS messages can be sent to phones from the Internet, if you use special programs.

Messages from the phone are sent to a Short Message Service Center (SMSC) which provides a store-and-forward mechanism. The Center attempts to send messages to the requested recipients. If a recipient is not reachable, the Center queues the message for later retry. Some SMSCs also provide a “forward and forget” service where transmission is tried only once. Message delivery is “best effort” so there is no guarantee that a message will actually be delivered to the recipient. Delay or complete loss of a message is not uncommon, particularly when sending between networks. Users may choose to request delivery reports, which can provide positive confirmation that the message has reached the intended recipient, but notifications for failed deliveries are unreliable at best.

Despite a low cost to consumers, SMS is enormously profitable to service providers as compared to voice communication. The same network can accommodate hundreds of SMS messages instead of one minute of voice communication often priced as one SMS. Hypothetically, at a typical length of 190 bytes (including protocol overhead), more than 350 SMS messages can be transmitted per minute at the same data rate (9 kbit/s) as a usual one minute voice call.

Although channels for voice and service information are separate, and the voice channel does not usually clog, it is important to know that the service data channel used by SMS can get clogged by a large volume of data, inhibiting the dialing of a regular voice number.

How to Use

In order for a phone to send and receive SMS messages, the mobile operator’s phone number for the SMS center (SMSC) must be entered in the phone settings. In majority of cases, this number is already preset into the SIM (Subscriber Identity Module) card, so there is no need to enter it manually.

Incoming SMS are saved in Incoming Messages folder (or one with a similar name) where one can view them. Some phone models save this folder to a SIM card therefore limiting the number of saved messages to dozens. When the folder reaches its size limit, SMS messages will stop reaching the user.

Modern phones, however, save the folder in the phone memory which is usually much larger than the size of the SIM memory. Sent messages are saved in Sent Messages folder; also there are folders for Outgoing and Draft messages.

To send an SMS message from a regular mobile phone, one usually has to use the tiny phone’s numerical keyboard. Inputting of a letter is done by sequential pressing of a key, or with a help of some system of predictive input like T9 or iTAP that suggest possible words using the beginning of the word. Some advanced phone models have alpha-numerical keyboards that significantly simplify typing. Smartphones and communicators often feature an on-screen keyboard.

Length of an SMS Message

SMS text can contain alpha-numerical symbols, i.e. letters and numbers. The maximum length of a message in the GSM standard is limited by 140 bytes. Therefore for 7-bit coding (Latin alphabet and numbers), a message can contain up to 160 symbols. For 8-bit coding (German, French languages), a message is limited by 140 symbols. Other alphabets (Chinese, Arabic, Russian, etc.) use 2-byte coding UTF-16. Therefore, an SMS message in these languages (Cyrillic, for instance) cannot be longer than 70 symbols.

Segmented messages help to alleviate the maximum length problem. The segment number and the total number of segments are written in the user data header (UDH) of a segmented message. However, segmented messages are not supported by all phones. Even those that support them often limit the number of segments in a message to 3 or 5. A telephone which does not support segmented messages will display each segment as a separate message. As a rule, every segment is priced as a single message.

A phone keyboard is not fun for long messages, so people often use abbreviations, omit vowels, or substitute numbers and letters for similar sounding words and syllables. For example, «C u l8r» can well substitute «See you later». See http://www.teenchatdecoder.com/ for help with abbreviations.

In Russia SMS messages are often written in “Translit” (in Russian language but in Latin letters). This custom originated on phones which had no Cyrillic support.

Popularity

In the world, there are twice as many people using SMS than email. According to CTIA, over 28.8 billion text messages are sent per month, totaling almost 241 billion per year (June 2007, www.ctia.org).

Short message services are developing very rapidly throughout the world. In 2000, only 17 billion SMS messages were sent; in 2001, the number was up to 250 billion. 2004 was a record year with 500 billion SMS messages. At an average cost of USD 0.10 per message, this generates revenues in excess of $50 billion for mobile telephone operators and represents close to 100 text messages for every person on the planet.

SMS is particularly popular in Asia (excluding Japan), Europe, Australia, and New Zealand.

Asia and the Pacific

The Philippines is known as the ‘text capital of the world’. Presently each mobile phone user in the Philippines is sending at least 10 text messages a day compared to about 3 text messages per user in the United Kingdom.

In 2001, text messaging played an important role in deposing former Philippine president Joseph Estrada.

At the end of 2007 four of the top mobile phone service providers in the country stated that there were 42.78 million mobile phone subscribers in the Philippines or about one Filipino in two is a subscriber to a mobile phone service.

Affordability is one of the main reasons why text messaging has become so popular in the Philippines. Another reason is that text messaging is generally more reliable as compared to a fixed line or mobile service.

In the Philippines, on average, 400 million text messages are sent daily or approximately 142 billion text messages are sent per year. It is more than the annual average of any European country, China, or India.

In China SMS is very popular (18 billion short messages were sent in 2001), making China Mobile number two company in the world in terms of data revenue in 2007.

SMS is hugely popular in India, where youngsters often exchange lots of text messages, and companies provide alerts, infotainment, news, cricket scores update, railway/airline booking, mobile billing, and banking services through SMS. There have also been very interesting economic effects of SMS in rural Indian communities where farmers gained access via SMS to information about effective crop prices in urban centers (http://manjerok.ru/blog/archives/3).

Short messages are particularly popular among young urbanites in the Pacific due to attractive prices. For example, in Australia a message typically costs between AUD 0.20 and AUD 0.25 to send (some pre-paid services charge AUD 0.01 for within-the-network messages) as compared to a voice call which costs somewhere between AUD 0.40 and AUD 2.00 per minute (commonly charged in half-minute blocks).

Mobile Service Providers in New Zealand, such as Vodafone and Boost Mobile, offer up to 2,000 SMS messages for NZ$10 per month. Users on these plans send on average 1,500 SMS messages every month.

Europe

Europe follows Asia in terms of SMS popularity. In 2003, on average, 16 billion messages were sent each month.

Users in Spain on average sent a little more than fifty messages per month in 2003. In Italy, Germany, and the United Kingdom the figure was around 35–40 SMS messages per month. In each of these countries the cost of sending an SMS message varies from as little as £0.03 to £0.18 depending on the payment plan.

Curiously, France has not taken to SMS in the same way, sending on average just under 20 messages per user per month. France has the same GSM technology as other European countries so the uptake is not hampered by technical restrictions.

In the Republic of Ireland, a total of 1.5 billion messages are sent every quarter, on average 114 messages per person per month. In the United Kingdom over 1 billion text messages are sent every week.

USA

In the United States, however, the appeal of SMS is more limited. Although an SMS message usually costs only US$0.15 (many providers also offer monthly text messaging plans), only 13 messages were sent by an average user per month in 2003.

In the US, SMS is often charged both at the sender and at the destination, but it cannot be rejected or dismissed, as opposed to the phone calls. The reasons for this are varied—many users have unlimited “mobile-to-mobile” minutes, high monthly minute allotments, or unlimited service. Moreover, push to talk services offer the instant connectivity of SMS and are typically unlimited. Furthermore, integration between competing providers and technologies necessary for cross-network text messaging has only been available recently. Some providers originally charged extra to enable use of text, further reducing its usefulness and appeal. The relative popularity of e-mail-based devices such as BlackBerry may also be responsible for weakness of text messaging.

Notwithstanding the dire initial uptake of SMS, voting on a TV show American Idol has introduced many Americans to SMS. In 2005 season of the show, 30 percent of sent SMS were from the first time users. That year the total number of SMS votes made American Idol #1 TV show in the world in terms of SMS interactivity. In 2006 there were 120 million cross-operator SMS votes.

Latest 2007 statistics by Sharma (http://www.chetansharma.com/usmarketupdateq407.htm) reveal that “Verizon with $7.4B, AT&T with $6.9B, and Sprint with $5.2B in data services revenues stood at #4, 5, and 6 in the world. AT&T became the second US operator after Verizon to be in the select group of five global operators (the other three are NTT DoCoMo, China Mobile, and KDDI) who are now generating $2B or more in data revenues per quarter. Non-messaging data revenues continue to be in the 50-60% (of the data revenues) range for the US carriers.”

Although texting is widely popular among young people, its use is increasing among adults and business users as well. According to both the Mobile Marketing Association and Pew Internet & American Life Project Surveys, 40% of cell phone owners use text. The split by age is as follows: 13-24’s: 80% text, 18-27’s 63% text, 28-39’s: 31% text, 40-49’s: 18% text. The amount of SMS being sent in the United States has gone up over the years as the price has gone down to an average of $0.10 per text sent and received. Many providers also make unlimited texting available for an affordable price.

In order to convince more customers to subscribe to text messaging plans, some major operators have recently increased the price to send and receive text messages to $0.15 – $0.20 a message.

Finland

The first SMS typed on a GSM phone is claimed to have been sent by Riku Pihkonen, an engineering student at Finnish Nokia, in 1993.

Many interesting TV innovations have become widespread in Finland. TV channels have introduced “SMS chats” when a viewer can send an SMS to a phone number to have his or her message broadcasted on the TV a while later. Chats are always moderated that prevents having harmful material sent to the channel. The TV-SMS craze has become very popular and it has also evolved into TV-interactive games, quizzes, and strategy games. TV games usually start by registering one’s nickname. After that a viewer can send short messages to control his/her character on the TV screen. Messages usually cost 0.05 to 0.86 Euro apiece, and a usual game requires a player to send dozens of messages. In December 2003, a Finnish TV channel, MTV3, put a Santa character on air reading aloud messages sent in by viewers. More recent late night attractions on the same channel include “Beach Volley”, in which the bikini-clad female hostess blocks balls “shot” by short messages. Finland has launched the very first entirely “interactive” TV-channel “VIISI” on March 12, 2004 that in November 2004 was acquired by SBS Finland Oy and turned into a music channel named “The Voice”.

In 2006, Prime Minister of Finland, Matti Vanhanen, made front page news when he allegedly broke up with his girlfriend using a text message.

In 2007 Finnish author Hannu Luntiala presented a 332-page novel The Last Messages about a fictitious IT-executive in Finland who resigns from his job and travels throughout Europe and India, keeping in touch with his friends and relatives only through text messages which are listed in chronological order in the novel.

Japan

Japan was among the first countries to widely adopt short messages, with pioneering non-GSM services including J-Phone’s “SkyMail” and NTT Docomo’s “Short Mail”. However, short messaging has been largely rendered obsolete by the prevalence of mobile Internet e-mail, which can be sent to and received from any e-mail address, mobile or otherwise. That said, while usually presented to the user simply as a uniform “mail” service (and most users are unaware of the distinction), the operators may still internally transmit the content as short messages, especially if the destination is on the same network.