Yakov Shafranovich <research@solidmatrix.com> writes:
There is no reason why cell phone companies around the world could
not have developed a separate messaging framework NOT based on SMTP
and email.
SMS (at least in GSM-based networks) differs a lot from email: limited
size, messages may be discarded etc. It's certainly not similar to
SMTP.
And with SMS I don't think there's any way to prevent the sender knowing
their message was successfully delivered if they sent it with a delivery
receipt. Ideal for spammers unfortunately.