3 ms·

Looks like there is a TP-PID field that has values to indicate replace message: https://security.stackexchange.com/questions/19731/how-does-a-new-sms-message-o

Looks like there is a TP-PID field that has values to indicate replace message: https://security.stackexchange.com/questions/19731/how-does-a-new-sms-message-overwrite-a-previous-one https://security.stackexchange.com/questions/19731/how-does-... I find this fascinating; I didn't know this functionality existed.

082349872349872 4y ago
Aha, not "same PID", but "special PID": https://en.wikipedia.org/wiki/GSM_03.40#Protocol_Identifier https://en.wikipedia.org/wiki/GSM_03.40#Protocol_Identifier (65-71) also potentially interesting: is there a no-notification ping? Sometimes I am glad I grew up in the fixed-line era. > Short Message Type 0 is known as a silent SMS. Any handset must be able to receive such short message irrespective of whether there is memory available in the (U)SIM or ME or not, must acknowledge receipt of the message, but must not indicate its receipt to the user and must discard its contents, so the message will not be stored in the (U)SIM or ME.