The Short Message Peer-to-Peer (SMPP) is an open, industry-standard protocol used in telecommunications industry in order to establish and exchange messages between messaging platforms and Short Message Service Centers (SMSC).

Bind supports version 3.4 of the SMPP protocol

Establishing connectivity

The following parameters are required in order to establish the connectivity to Bind platform

You can establish the connection by any of the following bind types:

• bind_transmitter (able to send messages but unable to receive delivery reports)
• bind_transceiver (able to send messages and receive delivery reports)
• bind_receiver (able to receive delivery reports)

Supported PDU's (Protocol data units)

The following PDU's are supported:

• bind_transmitter
• bind_transceiver
• bind_receiver
• submit_sm
• deliver_sm
• enquire_link
• unbind

Enquire link

Once bound the enquire links are going to be exchanged between two connected parties with a default value of 30 seconds between the PDU. Both parties can send enquire link pdu's in order to keep the connection alive when there is no other pdu's being exchanged.

Message encoding

The following data coding values are supported:

• 0 - GSM7
• 1 - Latin1
• 8 - Unicode/UCS-2

Message length

• GSM7 encoded messages longer than 160 characters will have a maximum length of 153 characters per PDU, the rest of the payload is being used for UDH (User data header)
• Unicode/UCS2 encoded messages longer than 70 characters will have a maximum length of 67 characters per PDU, the rest of the payload is being used for UDH (User data header)

User data header (UDH) is a part of the PDU used to carry the meta information such as count of messages expected along with the information about the current message.

Command status

The following command status values are being returned by the SMPP server:

bind_resp

submit_sm_resp

Delivery reports

When bound with bind_transceiver and bind_receiver your SMPP session is going to receive deliver_sm PDU's in cases where the destinations and suppliers support them.

The deliver_pdu message has the following format:

id: c4c1749d-96ff-419a-b828-9d307a277c4e sub:001 dlvrd:001 submit date:2302181515 done date:2302181515 stat: DELIVRD err:000 Text:

Where:

• id - represents the message id received on submit_sm_resp
• sub - indicates whether the message was successfully submitted
• dlvrd - indicates whether the message was delivered
• submit date - provides the date of submission
• done date - provides the date of delivery
• stat - represents the state of the message, where possible values are:
  • DELIVRD
  • UNDELIV
  • EXPIRED
  • UNKNOWN
  • REJECTED

The following error codes can be received as a part of delivery report PDU within err field: