
Why text messages are limited to 160 characters - soundsop
http://latimesblogs.latimes.com/technology/2009/05/invented-text-messaging.html
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cuerty
There is a technical aspect of the GSM encoding that most people doesn't know:
It's just 140 bytes. In most encodings (the way computers represent text as 0
and 1) one character of the english language can be seen as a byte, this is
because the 8 bits of the byte are used to represent 256 numbers that are
mapped to letters, since there is less than 127 characters (leters and
symbols) in the english alphabet, the GSM encoding use only 7 bits (less than
a byte!) to represent the letters, and taking adventaje of those bits left it
finds the way to have 20 more characters than bytes.

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wvenable
This doesn't seem to jive with the generally accepted reasoning for the 160
character limit.

From Wikipedia:

The key idea for SMS was to use this telephony-optimized system and to
transport messages on the signalling 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 without
additional cost. However, it was necessary to limit the length of the messages
to 128 bytes (later improved to 160 characters), so that the messages could
fit into the existing signaling formats. Therefore the service was named
"Short Message Service"

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cliff
I think that both this article and the Wikipedia article are correct.

The LA Times took the more human-centric approach to the story, which from a
technical perspective was just 'how many and which characters can we cut out
to maximize the 128 bytes available'. It also highlights the person (or the
person who lead the team of people) who actually extended the SMS control
channel to include text messages.

I think that overall the story told by the LA Times is probably a lot more
interesting to its readers than the tech behind it.

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geeko
This article makes me think back of my first venture I started with a friend
of mine during university. We developed a j2me app which compressed the sms
and allowed you to write roughly 400 characters within one sms while still
only paying for one. Learned a lot on the way and will always think back of it
as being my most exciting "course" at uni (In fact I'm thinking on how to
revive it these days, but still very unsure).

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ableal
About who and why, back in 1985. Didn't know someone had actually 'tested' the
message length.

