Why are SMPP concatenated messages not delivered?

Symptom

Why are SMPP concatenated messages not delivered? The individual parts of a concatenated message are processed but the user did not receive the whole message.

Applies To

• SMPP
• Concatenated Messages
• Multiple Servers

Resolution

Customers who are connected with multiple SMPP servers must make sure that all parts of concatenated message sent by SMPP are sent through the same SMPP server. This will ensure all the parts of the message identified based on the same UDH Reference Number, are sent via the same gateway.

Parts of a concatenated message received in different servers may be sent via different gateways which will lead to the message not sent to the end-user.

Example: Concatenated messages with two parts received via both smpp1 and smpp2 server with UDH Reference number: XX

• Part 1 Message: UDH 050003XX0102 - Received in smpp1 - executed via Gateway 1
• Part 2 Message: UDH 050003XX0202 - Received in smpp2 - executed via Gateway 2

Gateway 1 is waiting for the second part of the concatenated message whereas Gateway 2 is waiting for the 1st part of the message. Since neither of the Gateways receives all the parts, the concatenated message is not delivered to the end-user.