High Quality Content by WIKIPEDIA articles! The Short Message Service is realised by the use of the Mobile Application Part (MAP) of the SS#7 protocol, with Short Message protocol elements being transported across the network as fields within the MAP messages. These MAP messages may be transported using `traditional` TDM based signalling, or over IP using SIGTRAN and an appropriate adaptation layer. The Short Message protocol itself is defined by 3GPP TS 23.040 for the Short Message Service - Point to Point (SMS-PP), and 3GPP TS 23.041 for the Cell Broadcast Service (CBS).