ABSTRACT
PA (Public Address) and VA (Voice Alarm) systems have evolved very much in the last years. These systems are mixing the need for a safe Voice Evacuation System with the needs of daily basis functionality and adaptability to the end user requirements.
To ensure the functionality of the VA part there are some standards like EN 60849, EN54-16, SS546:2009(CP25) and others that provide enough objective criteria to define the requirements for each country and application. For the general PA/VA systems there are some key factors that are becoming very important. The purpose of this speech it to talk about this factors that are:
Transmission backbone topology, and how this will determine if we use Audio Over Ethernet and Audio Over IP. What are the differences between them and what are the limitations and advantages of using Audio Over IP.
Backbone Bandwidth usage and how this will affect the type of Audio that is sent through the network. Using license free compression audio formats (Ogg-vorbis). Storing messages at the station level in order to prevent high bandwidth usage during peak hours of network traffic.
Direct Integration with Passenger Information System, skipping the bottle necks created by gateway equipment, often computers, and permitting the Passenger Information Systems to talk directly to the PA/VA hardware.
