The term SMS (acronym of: short message service based on technology-wiki) is commonly used to indicate a short text message sent from one phone to another, with a small fee. The correct term would be SM (Short message), but has now established use to indicate the single message with the name of the service.
The service was originally developed on the GSM network, however it is now also available on other networks such as UMTS and some fences (in Italy for now just Telecom). You can send SMS to a mobile phone from a computer, over the Internet, and the landline phone.
Among the main advantages received SMS, underlying the extraordinary diffusion of this service as communication system, there is the low cost compared to a long phone call and the opportunity to make asynchronous communication, that is, to read the message at any time following receipt; SMS is also very popular to send wishes in case of recurrences (thanks to the convenience of automatically sending to multiple recipients) or for other types of relational approaches, in that particularly discreet and then easier to manage, especially for the more timid.
The first text message of the story was sent on December 3, 1992 from a computer to a mobile phone on the GSM network Vodafone English and the text of the message was “MERRY CHRISTMAS”. The first SMS from mobile to mobile instead was sent in early 1993 from an intern at Nokia.
The standard provides for two different types of messages: those point-to-point (SMS/PP), used in communication from one terminal to another, and those type Cell Broadcast (SMS/CB), originated in a cell and distributed to all terminals under its coverage.
The message has a fixed size of 140 bytes. This translates in practice into the possibility of using 160 text characters (7-bit). In languages that use other characters than the Latin alphabet, for example in Russian, Chinese, Japanese, the message is limited to only 70 characters (each of 2 bytes, using Unicode).
From the point of view of transmission, SMS message data units (6 different PDU Protocol Data Unit are employed) are inserted into the GSM control channels, so that you can receive or send a message in a conversation.
In particular point-to-point Messages are messages that a user can send to another user of the mobile network. Each message is sent to a Service Centre (SMSC, Short Messages Services Centre) which in turn is concerned to send it to the appropriate terminal, if the same GSM network, or the network operator service center of the recipient. Therefore the single message is actually divided into two: the message from the terminal to the Service Center (SMS-MO Mobile Originated), and the recipient Service Center (SMS-MT Mobile Terminated). Purpose of the SMSC is obviously the one to do the store-and-forward messages, even in anticipation of a possible temporary inaccessibility of the recipient.
Given that the connection between terminal and service center is connectionless, there is no guarantee nor about sending or receiving SMS messages. However you can apply for a “return receipt”, the Status Message Reports. In this way, once the message is successfully forwarded to the recipient, it sends a “message delivered” to the sender. This service typically doubles the price of each SMS.
From the point of view of content that can be sent, sometimes cell phones allow sending concatenated messages larger than classic 160 characters, actually multiple SMS shipped independently and reassembled at the reception: depending on the operator, the cost of the service to the user rises, as a message format for example from 2 SMS can be counted and paid like 2 SMS. Also the number of characters available does not double, why some bytes are used for the information necessary for the concatenation; in practice the number of characters useful for message is reduced to 320 306 than you have available with two separate messages.
The use of SMS messages has spread very quickly throughout the world. In mid-2004, the volume of annual traffic worldwide was about 500 billion SMS; the growth of the phenomenon is impressive when you consider that in 2000 there were approximately 17 billion messages. In 2008, instead they were sent the beauty of 2.5 trillion (all zillion corresponds to 1000 billions) of SMS. The more widespread the use of the service is found among young people, particularly in urban areas. SMS is more popular in Asia, Europe and Australia than the United States. SMS business grows every year and is a bargain for companies that, for years, do not lower prices.
Because of the limitations on the length of the message and its inconvenience of introducing texts with the tiny keyboard normally available on cellphones, text messages are often written in a concise and full of abbreviations language, similar to that used in Internet chat. A typical example is the use of “6” instead of the word “six” (voice of the verb to be). The same phenomenon occurred with different extension and form in all languages. In English often omits the vowels (for example: “txt msg” means text message, text message). In Russia to prevent the use of the Cyrillic alphabet, which uses the Unicode system and limits the length of the message to 160 characters instead of 70, one often uses the Latin alphabet to transcribe Russian. The use of numbers or combinations of numbers and letters instead of words sound the same is also widespread in other languages; in English “4U” (four u) means “for you” (for you).
The use of abbreviations declined with the introduction of algorithms based on frequency of use of the words, trying to guess the word that you want to type in before it has finished composing it entirely (T9 dictionaries) and that reduce the time necessary for the introduction of the text; This makes it less useful abbreviations and more laborious to use because you are not in the dictionary, however not all words are recorded in the dictionary, and it is sometimes necessary to manually add new ones, or compose them instantly through other words or parts of them (eg. an adverb as “manifestly” could be generated by the Union of “hands”, “party” and “mind”, three words certainly present in dictionaries and T9). The spread of T9 is highly differentiated from country to country, for example as exists in Italy because of low use in Slavic countries.