SMPP defines three modes of operation for an ESME: transmitter, receiver and transceiver.
When connecting to Nexmo SMPP API you should select one of these modes of operation:
- Transmitter / receiver mode: capable of submitting messages, querying the status of messages and system parameters but it is not able to receive short messages.To be capable of receiving delivery receipts of short messages, it will be necessary also to bind as a receiver.
- Transceiver bind: SMPP version 3.4 introduced the transceiver type of connection. It is similar to having a transmitter and receiver connection over the same network link and allows submitting and receiving.
We suggest using transceiver bind when possible as it helps to maximise the amount of network links (connections) available for your account (by default is 2).