Application-to-Person Messaging (A2P)
A2P messaging is SMS or other messaging sent from a software application to a person's phone, such as one-time passcodes, alerts and marketing.
What is Application-to-Person Messaging (A2P)?
Messages sent the other way, from a person to an application, are P2A. A2P traffic is usually delivered through aggregators connected by SMPP and is a significant revenue line for mobile operators, which also police it for fraud such as artificially inflated traffic.