Summary of SMS history

In1990 the European Telecommunication Standards Institute public specifications of the then new GSM system. In this specification was introduced to a sub-protocol, initially little known because little publicized.


None of the experts, in the early '90s, he never imagined that a service for sending short text messages (Short Message Service, SMS precisely) would have been so successful in the future.
Designed initially as a service for the distribution of broadcast information, it also had the ability to send short messages between terminals: no one believed it, because it seemed too complicated and exhausting Write a message using only the buttons on a phone and T9 was not even on the horizon.


What then is an SMS? This is a simple text message of up to 160 characters, 7 bit format.
Are exchanged between mobile phone and SMSC (Short Message Service Center) and between SMSC, are delivered using the signaling channel, thus allowing reception even when the channel voice / data are already committed.


SMS are received from the terminal with a set of data 'accessories': well (of course) to the text of the message, the SMSC sends the mobile phone among other things, the number of the sender and the number of the gateway used. In the Protocol, however, not enter any authentication system, so you can be sure that the number of the sender is really the one received, the sender is in fact sent by the terminal itself all SMSC, and there actually a way to change it.