What Does Short Message Peer-to-Peer (SMPP) Mean?
In IT, Short Message Peer-to-Peer (SMPP) is a type of protocol that allows for the transmission of a significant volume of SMS text messages. Typically, SMS text messages go through an SMPP, which can be used to connect external systems to a message center handling high SMS volumes.
Techopedia Explains Short Message Peer-to-Peer (SMPP)
Some of the terminology around SMPP can be confusing. For example, definitions of SMPP make reference to External Short Messaging Entities (ESMEs), which are actually a type of application that could be called a "proxy" that connects to a short message service center and sends and/or receives short text messages. One informal definition of an ESME is that, when individual cell phone holders get SMS text messages that did not come from another user physically typing in a particular SMS message, they are often getting SMS messages from ESMEs.
In general, SMPP uses TCP/IP or a related protocol to connect to the message center and to deliver or receive SMS from users.