How Does SMS Service Actually Work?

Short message service (SMS) is a wildly popular feature
available on most digital mobile phones. SMS allows users to
send short messages to other cell phones. These short messages
are called text messages. SMS was invented by a Finnish civil
servant named Matti Makkonen. Many people understand what SMS
is, but few understand how it actually works.

In SMS, messages are sent with a "store-and-forward" mechanism.
The messages are sent to a Short Message Service Center (SMSC),
and then relayed to the intended recipient. If the messages do
not reach the recipient upon the first attempt, then the SMSC
will try again. It is important to understand that SMS delivery
is not guaranteed. Many messages cannot be delivered, but the
delivery is called "best effort." The amount of attempts to send
a text message varies with the company.

SMS messages are transmitted via SS7 within the standard GSM MAP
framework. SMS messages have a certain payload length. The
signaling protocol is precisely 140 bytes. In simple terms, SMS
messages have very constrained character limits. This is why
messages are sent in "txt speak." Text speak is the practice of
shortening words and phrases in order to fit messages into the
allowed amount of bandwidth. SMS messages cost different amounts
in different countries. In the United States, the average
message costs 10 cents.

Text messages do not always have to be sent from mobile phone to
mobile phone. AOL Instant Messenger has an option that will send
instant messages to a cell phone. Additionally, there is a
widget available for Mac OS X Tiger that will allow a user to
send text messages to a cell phone from the dashboard. SMS
messages can also be utilized to give news alerts. Additionally,
SMS messages can be used to give sports updates and statistics.
In this way, SMS messages are very versatile. 

Technology is constantly evolving. SMS services prove that
communication is becoming broader and easier. Technologists
predict that SMS service will advance such that the service will
be more reliable, and be able to store more data for the purpose
of transmission.