But this begs the next question: What precisely does the SCTS (Service Centre Time Stamp) mean?
Is it the time that the Service Centre first receives the message?
Is it the time that the Service Centre first attempts to forward the message for delivery?
Is it the time of the most recent attempt to forward the message for delivery?
Or what??
Also, the name implies that the timestamp is applied by/at the Service Centre - so what are the delays that could be experienced before the message is actually received?
Without knowing these things, it seems to me that this technique is worthless?
There is no guarantee on the delivery time of an SMS. So it even could take hours until you actually receive the message. (This of course is not normally the case, but it may happen and I already witnessed it myself…)
I would assume that the message is time stamped when the Service Center accepted it for delivery. When we had long delays the messages did not arrive with a current time time stamp. It did seem closer to the time the message was actually sent…
How about this:
You could connect to the “Physikalisch-Technische Bundesanstalt” either through TCP/IP or data call and get the time pretty accurate. The only delay will be caused by TCP/IP traffic or data call signal run times. That should not exceed a few seconds…
