In the image above, both the sender and receiver of the SMS messages are subscribed to a mobile operator. Once the SMS message is sent from the sender’s mobile phone, the SMS is sent to the network operator and is then delivered to the recipient’s mobile phone.
A2P (application-to-person) messaging on the other hand is the process by which messages are sent from an application, usually a web-based platform, to a mobile user. Messages that do not originate from a mobile device with a SIM card are regarded as A2P messages (excluding only Call Me messages).
As can be seen in the infographic above, the process involved in sending an A2P SMS message is very similar to that of sending a P2P SMS message. The key difference between the two is that the SMS message is now being sent from an application rather than from a mobile phone.