Reference section - SMPP
enquire_link
SMPP enquire_link
SMPP (Short Message Peer-to-Peer) is an open, industry standard protocol designed to provide a flexible data communications interface for the transfer of short message data between External Short Message Entities (ESME), Routing Entities (RE) and Message Centres (MC). The SMPP protocol is a means by which applications can send SMS messages to mobile devices and receive SMS from mobile devices.
4.1.2 Enquire Link Operation
This PDU can be originated by either the ESME or MC and is used to provide a confidence check of the communication path between an ESME and a MC. On receipt of this request the receiving party should respond with an enquire_link_resp, thus verifying that the application level connection between the MC and the ESME is functioning. The ESME may also respond by sending any valid SMPP primitive.
The enquire_link can be sent when the session is in the open, bound (TX, RX or TRX), unbound or outbound states. Typical values for the period of inactivity before the ESME or MC originate this operation are between 30s and 120s.
4.1.2.1 enquire_link Syntax
| Field Name | Size Octets | Type | Description | Ref. |
| command_length | 4 | Integer | Defines the overall length of the PDU. | 4.7.4 |
| command_id | 4 | Integer | 0x00000015 | 4.7.5 |
| command_status | 4 | Integer | 0x00000000 | 4.7.6 |
| sequence_number | 4 | Integer | Set to a unique sequence number. The associated enquire_link_resp PDU should echo the same sequence number. | 4.7.24 |
4.1.2.2 enquire_link_resp Syntax
The enquire_link_resp PDU is used to reply to an enquire_link request.
| Field Name | Size Octets | Type | Description | Ref. |
|---|---|---|---|---|
| command_length | 4 | Integer | Defines the overall length of the PDU. | 4.7.4 |
| command_id | 4 | Integer | 0x80000015 | 4.7.5 |
| command_status | 4 | Integer | 0x00000000 | 4.7.6 |
| sequence_number | 4 | Integer | Set to the same sequence number of original enquire_link PDU. | 4.7.24 |
SMPP Tools and Services
Services from Melrose Labs (e.g. Tyr SMS Gateway and SMPP SMS Gateway ) support SMPP v5 and the earlier versions, v3.3 and v3.4.
SMSC Simulator
Looking to test your SMS application or SMS-enabled application before connecting to a live SMS gateway or SMSC? SMSC Simulator enables you to test using SMPP v3.3, v3.4 and v5.
Read more about SMSC Simulator >
SMPP Clients
Send and receive SMS using an SMPP account and browser-based SMPP client.
- SMPP Client * - send/receive SMS and perform other SMPP operations
- SMPP Sender * - basic send SMS client
- SMPP Multi-Sender * - send SMS to multiple numbers from a CSV or spreadsheet
- SMPP Chat * - one or more two-way conversations using SMS and SMPP
- Message Broadcast - text messaging portal for use with any SMPP-capable messaging provider
* SMPP session between web browser and provider.
SMS Code Bench
SMS messaging code sample and development playground. Collection of editable and runnable code samples in a variety of languages for different SMS interactions.
SMS Code Bench >
Send SMS programmatically with SMPP
Send SMS programmatically with SMPP using Python, Java, Go, Perl, C++, C#, Node.js, Ruby and PHP.
SMPP Load Test
Perform an SMS load test using SMPP from your web browser and view the results in realtime. SMPP Load Test tool submits SMS messages using SMPP at the specified rate. Messages are sent to one or more mobile numbers in a range from a single source address or range of source addresses.
Use the online SMPP Load Test tool >
SMPP Analyser
The SMPP Analyser acts as an SMPP proxy, with the client application binding to the service and the service onward binding to the SMSC or SMS Gateway. Packet captures can be viewed in your browser or exported into Wireshark.
Use the online SMPP Analyser >
Message Hub
Message routing between applications (uses SMPP protocol). For use in IoT, chat applications, asyncronous notification in web applications, and other applications.
Message Hub documentation >