SHORT MESSAGE TRANSMISSION METHOD AND SYSTEM, AND SHORT MESSAGE GATEWAY MOBILE SWITCHING CENTER DEVICE

The present disclosure provides a short message transmission method and system, and a short message gateway mobile switching center device. The short message transmission method comprises: after receiving a short message transmitted by a user terminal, transmitting a query request to a unified data management (UDM) entity, so that the UDM entity queries an identifier used for indicating whether a relay network element supports a short message service interface; after receiving a routing query response transmitted by the UDM entity, extracting, from the routing query response, the identifier used for indicating whether the relay network element supports the short message service interface; according to the identifier, determining whether the relay network element supports the short message service interface; and if the relay network element supports the short message service interface, transmitting the short message to a short message service function (SMSF) entity by means of the selected relay network elemen