This document defines a platform-specific model (PSM) for data exchange, which specifically uses ASN.1 and TCP/UDP (transmission control protocol/user datagram protocol) datagrams which were defined as "DATEX-ASN" in the first edition of this document for AP-DATEX (application profile-data exchange) and other Internet protocol (IP) networks. A PSM is an actual implementation of a platform-independent model (PIM) for exchange. This document specifies the message rules and procedures for communication between different systems for ITS using TCP/UDP datagrams.

This document deals mainly with the communication interfaces. It has been designed to meet the unique requirements of intelligent transport systems (ITS). However, it has also been designed in a generic fashion and thus can be used for other data exchanges as well.