BS 8521:2009 Specification for dual-tone multi-frequency (DTMF) signalling protocol for social alarm systems
BS 8521 specifies requirements for the transfer of information and controls within a social alarm system, by means of dual-tone multi-frequency (DTMF) tone signals passing between site control or local equipment and an alarm receiving centre via the public switched telephone network (PSTN) supporting voice traffic conforming to ITU-T Recommendation G.711.
BS 8521 specifies an in-call protocol which supports the 300 ms maximum round trip delay specified in the UK National Transmission Plan for connections over the fixed network.
Contents of BS 8521:
- Foreword
- Introduction
- Scope
- Normative references
- Terms and definitions
- Information transfer
- Communication
- Speech path and system control commands
- Programming
- Remote access to local unit and controller (incoming calls)
- Bibliography
- Diagrammatic representation of an example of an alarm transmission protocol
- Diagrammatic representation of an example of local unit and speech communication
- Diagrammatic representation of an example of programming
- ARC initiated communications sequence with controller
- ARC initiated communications sequence with local unit and controller