Telecommunication terminal for push-to-talk-over-cellular telecommunication system, adds message validity information item indicating whether telecommunication session message is valid, to telecommunication session message

摘要

The terminal (101) has telecommunication session unit for setting up and controlling half duplex telecommunication session. A telecommunication session message generation unit generates and transmits telecommunication session message, which adds message validity information item indicating whether the telecommunication session message or another telecommunication session message identified in the generated message is valid, to generated message. Independent claims are included for the following: (1) telecommunication system; (2) telecommunication session server unit; (3) method for generating and sending telecommunication session message; (4) computer readable recording medium storing program for generating and sending telecommunication session message; (5) computer program element for generating and sending telecommunication session message; and (6) computer program element for managing telecommunication session message.