
There are tamper-proof or tamper-envelopes that could make this safer.
Heh. I've seen the bills for those "outdated desktop with some software installed". You would not know they were outdated...
SMSCs _are_ expensive, regarless of what the
SMS is a good deal for the cellular carriers. In the beginning, it simply used the control channel to send messages back and forth, with a single, non-redundant SMSC.
All of a sudden, the service took off and costs increased (expansions in the control channel, adding cells, increasing bandwidth). Still, the profit margin is very healthy.
With all this considered, paying 10E-2 US$ for a SMS (actually twice, sender and receiver) is too much. The reasoning here is that the telco wants to force you to get a package of SMS, so that the money is on their pocket upfront.
And yes, I do come from a telco.
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