Feature request -- SMS spam blocking?

[Doug Sutherland]

Regarding SMS, a few basic comments on how it works ...
First, there is a message service center address, that is the 
link to the provider and is set with the +CSCA command.
The device (phone) can be set to allow originations (send),
terminations (receive) and broadcast type messages, set 
with the +CMCS (select message service). 

There is an alert called new message indicator, the behavior 
of which is set with +CNMI (New Message Indications).
There is command to list messages +CMGL. And yes there
is command to receive message +CMGR. 

The billing of messaging is entirely carrier dependent. 
There is no generic rule that can apply to everyone. 
Some carriers for example may not charge for incoming
messages while others will. As far as I know there is no
way to block specific origins in a way that would stop
billing of messages. So the answer is it is technically 
possibly to only receive (+CMGR) messages in your 
address book, that could be effective in blocking spam
messages, but afaik that has no impact on billing. How 
it is billed depends on your carrier, and which plan or
messaging feature you have.

Doug Sutherland
Proficio Research
http://www.proficio.ca/