Each module can send 6-8 SMS (with 160 char) per minute .
using DLR (Delivery receipt) will decrease the throughput to 4-5 SMS per minute .
in case of many IN SMS it can decrease the throughput.
Typically there is a limit to how many SMS can one SIM send per Day, Month.
in this case we can rotate the SIM up to 10 (4) SIM per port
in case the customer wants that the SIM will be active all the time, the SIM rotate is not an option
So the estimate throughput per module for day is : 7(SMS) * 60(minutes) * 12(Hour) = 5040
or with DLR 5(SMS) * 60(minutes) * 12(Hour) = 3600
in case the SIM will be limit by counter, we have the to check that the amount of SMS not pass this limit.
There are more parameters that can affect the throughput like rotate the SIM can take more than two minutes .
* all the calculation based on typical cellular network the throughput can be limited by the network (congestion, low BER ...)