> It is, but can be inhibited if need be. I have to say, SMS seems to
>> be GSM's achilles' heel. A lot of signalling functions on GSM appear
>> to be handled by thinly vieled SMS messages, stuff that would be
>> handled on a more formal level in CDMA through the paging channel.
> Are there on-line specs for GSM and/or CDMA ?
I'm sure there are. Google is your friend. :)
> I'm willing to bet that T-Mobile is unwilling to fully disable SMS
>> on an account because in many markets, they still use it for voicemail
>> and other notifications.
> Do they send the voicemail 'digitally compressed' [eg. simulated] ?
> What is the average bits/sec which they need ?
You misunderstand. I was referring to voicemail *notification*. As in, the voicemail icon on your phone? In CDMA, a flag is set on your handset via the paging channel. On T-Mobile and older generation GSM networks, the flag is not sent (though that is starting to change on T-Mobile, slowly). Instead, you get an explicit SMS message that reads something like "you have 1 unread voice mail message."
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