Is there a guaranteed delivery time for SMSes?
I am doing development on GSM modules and would like to know if the networks guarantee a maximum SMS delivery time. I have heard that this is around 8 seconds if the receiver GSM device is on when the SMS is sent. However, from a few tests, I have found that when sending two SMSes two a number (of a SIM in a GSM device) which is currently turned off, the one SMS may deliver within 60 seconds after registration and the other may not deliver at all (usually the newer one).
Furthermore, is there a way to request from the network to deliver SMSes after turning on?
I am doing development on GSM modules and would like to know if the networks guarantee a maximum SMS delivery time. I have heard that this is around 8 seconds if the receiver GSM device is on when the SMS is sent. However, from a few tests, I have found that when sending two SMSes two a number (of a SIM in a GSM device) which is currently turned off, the one SMS may deliver within 60 seconds after registration and the other may not deliver at all (usually the newer one).
Furthermore, is there a way to request from the network to deliver SMSes after turning on?