SMPP Connection Types – Sender, Receiver, Transceiver

When making a connection to an SMPP server, there are three different types of connections that can be supported.

• A “sender”, or “send only”, connection is allowed to transmit messages only over the connection, it cannot receive any messages. (Some SMPP servers will still deliver SMPP delivery receipt messages over a “sender” connection.)

• A “receiver”, or “receive only”, connection is not allowed to transmit messages over the connection, it can only receive messages. Any attempt to receive messages over this connection will usually result in the error ESME_RINVBNDSTS (Incorrect BIND Status for given command). If you see the ESME_RINVBNDSTS error when submitting messages, check to see that NowSMS has not been inadvertantly configured for a receiver only connection.

• A “transceiver” connection is allowed to both send and transmit messages over the same connection.

When defining an SMPP connection in NowSMS, it is possible to configure the connection to be only a “sender”, only a “receiver”, separate “sender” and “receiver” connections, or a single “transceiver” connection.

The type of connection that you use will depend on the preferences and policies of your SMPP service provider. Separate “sender” and “receiver” connections generally offer the best performance under extreme loads, however your provider may wish for you to use a “transceiver” connection to reduce the connection overhead on their server.

There are also special configurations where you may need to configure a connection to be only a “sender”, or only a “receiver”.

To define a “sender” connection only, ensure that the following settings are applied in the properties for the SMPP connection:

1. “Receive SMS Messages” must not be checked.
2. Under “Advanced Settings”, “Send and Receive Messages over the same connection” must not be checked.

To define a “receiver” connection only, ensure that the following settings are applied in the properties for the SMPP connection:

1. “Sender Address” should be left blank.
2. “Receive SMS Messages” must be checked.
3. “Support any outbound message traffic” must not be checked.
4. The “Preferred SMSC Connection for” list should be empty.
5. Under “Advanced Settings”, “Send and Receive Messages over the same connection” must not be checked.

To define a connection with separate “sender” and “receiver” connections, ensure that the following settings are applied in the properties for the SMPP connection:

1. “Receive SMS Messages” must be checked.
2. Under “Advanced Settings”, “Send and Receive Messages over the same connection” must not be checked.
3. Either “Support any outbound message traffic” must be checked, or there must be at least one entry in the “Preferred SMSC connection for” list.

The last setting may cause problems for configurations where you only want to route messages for sending via this connection explicitly (as described in “Routing SMS Messages to a Specific SMSC Route”). If you wish to only use explicit routing to route messages via this connection, add the text “explicit” to the “Preferred SMSC connection for” list, so the list will no longer be blank.

To define a “transceiver” connection, ensure that the following settings are applied in the properties for the SMPP connection:

1. “Receive SMS Messages” must be checked.
2. Under “Advanced Settings”, “Send and Receive Messages over the same connection” must be checked.

---

Related pages:

• Multiple SMPP Connections to One SMSC Although it is possible for SMPP Asynchronous connections to process hundreds of SMS messages per second, sometimes there are performance gains by...
• SMPP SMSC The gateway supports the SMPP (Short Message Peer to Peer) protocol, version 3.3 or 3.4, to connect to an SMSC...
• NowSMS Update – Interim Release 2010.05.07 An interim update release of NowSMS is available for download at http://www.nowsms.com/download/nowsmsupdate.zip. The most interesting updated features/capabilities include: Major SMS...
• Using NowSMS as an SMPP Server for Another Application One of the more unusual features of NowSMS is its ability to operate as an SMPP server. NowSMS can relay...
• Routing Options The “Routing Options” dialog for a modem connection contains a field to set the Phone Number of the GSM modem...
• SMPP Information and Resources SMPP (Short Message Peer-to-Peer) Protocol is an industry standard protocol that is used for exchanging SMS messages between peer entities....
• SMPP 3.4 Protocol Specification Archive For archive purposes, I’m posting a copy of the SMPP 3.4 Specification here. The SMS standards organization that created the...
• UCP/EMI SMSC The gateway supports the UCP/EMI (Universal Computer Protocol / External Machine Interface) protocol, version 3.5 or higher, to connect to...
• International Prefix Conversion for SMS There are many situations where end users submit messages using local number formats, but the upstream SMSC connection requires that...
• CIMD2 SMSC The gateway supports the CIMD2 (Computer Interface to Machine Distribution, version 2) protocol to connect to an SMSC over the...

---

Topic Category: SMPP, SMPP Async Mode, SMPP errors