This Global System for Mobile communications Technical Specification (GTS) has been produced by the Special Mobile Group (SMG) of the European Telecommunications Standards Institute (ETSI). This GTS outlines the use of data terminal equipment and specifies the terminal (DTE-DCE) interface for Short Message and Short Message Cell Broadcast Services within the digital cellular telecommunications system. The contents of this GTS are subject to continuing work within SMG and may change following formal SMG approval. Should SMG modify the contents of this GTS it will then be republished by ETSI with an identifying change of release date and an increase in version number as follows: Version 5.x.y where: y the third digit is incremented when editorial only changes have been incorporated in the specification; x the second digit is incremented for all other types of changes, i.e. technical enhancements, corrections, updates, etc. The specification from which this ETS has been derived was originally based on CEPT documentation, hence the presentation of this ETS may not be entirely in accordance with the ETSI/PNE Rules.