Traffic and Travel Information (TTI) - TTI via Transport Protocol Expert Group (TPEG) data-streams - Part 5: Public Transport Information (PTI) application (ISO/TS 18234-5:2006)
This Technical Specification describes the Public Transport Information (PTI) Application, which is intended to cover all modes of public (i.e. collective) transport as well as inter-urban and intra-urban travel. The application is designed to allow the efficient and language independent delivery of public transport information directly from service provider to end-users.
The term “application” is used in TPEG specifications to describe specific applications, such as in this case the public transport information application, which comprises three information containers: the message management container, the application event container and the TPEG-location container. The first two containers are fully described herein and the TPEG-location container is described in CEN ISO/TS 18234-6.
Each TPEG Application (e.g. TPEG-PTI) is assigned a unique number that is called the Application IDentification (AID). An AID is defined whenever a new application is developed. The AID is used within the TPEG-Service and Network Information Application (CEN ISO/TS 18234-3) to indicate how to process TPEG content and allows routing of data to an appropriate Application decoder.
AID = 0002 (hex) is assigned to the TPEG-PTI application, described in this specification.
The TPEG-PTI application aims at describing “legs” of a journey also described as “rides” by other methodologies. However, it is important to note that TPEG-PTI is not limited to describing single services, because it also allows the more general description of route, service and area-wide problems.
Public (or collective) transport information is usually consumed in one of four principle ways as follows:
-- Leader board information as used at stations or terminals;
-- A report on the state of a network;
-- The description of an individual service;
-- As a news flash report.