GL Releases Voice Recorder Emulator for VoIP Air Traffic Control

24 April 2018

Source: GL Communications Inc.Source: GL Communications Inc.GL Communications Inc., announced today its latest ED-137 Voice Recorder Emulator software, referred to as MAPS™ ED-137 Recorder Emulator.

Speaking to the press, Mr.Vijay Kulkarni, the CEO of the company said, “Air traffic control centers are required to provide continuous 'ground/ground' and 'ground/air' voice communication recordings with synchronized flight-related data, for establishing 'air traffic incident' chronology, replay, improving safety, audits, statistics and training purposes."

"ED-137/4B defines interoperability standards for the next-generation VoIP Air Traffic Recorder. These next-generation recorders are specially designed for all traffic control towers and centers to simplify the recording, archiving and playback of voice communications.”

He added, “MAPS™ ED-137 Recorder Emulator software emulates voice recording and replay of voice communication for VoIP ATM networks per EUROCAE ED-137B Volume 4 Standards. This software is an addition to the already existing test suite for VoIP ATM networks that includes, MAPS™ ED-137 Radio Emulators and MAPS™ ED-137 Telephone Emulators.”

Mr. Kulkarni further explained, “The software is designed to simulate Recorder Interface for both Air-to-Ground (AG) and Ground-to-Ground (GG) calls at Controller Working Position (CWP), Ground Radio Station (GRS) and Communication Recorders endpoints.

MAPS™ ED-137 Recorder supports Real Time Streaming Protocol (RTSP) to establish, terminate and maintain media sessions, which deliver media recording servers. Active recording requires an established session (i.e., a certain number of parameters that are exchanged between entities prior to any recording). CWP/VCS, Radio and Recorder use RTSP for such sessions. As RTSP relies on a transport layer protocol (TCP or UDP), these entities use SIP to exchange capabilities and connection information (i.e., IP address, port number and transport protocol).

Using MAPS™ ED-137 Recorder the following communication scenarios can be tested:

Simulate GRS/CWP entity to generate AG/GG recording sessions toward. Communication Recorders to test recorder functionalities.

Simulate VoIP ATM Recorder entity to receive and record voice from CWP/GRS to verify recorder functionality at CWP and GRS.

Important Features

  • Emulates ED-137/4B Recorder interface at CWP, GRS and Recorder endpoints
  • Simulates Recorder interface for multiple CWPs and Radios from single instance of MAPS™
  • Simulates Recorder interface for both Air-to-Ground and Ground-to-Ground calls
  • Supported codecs include G711 A-law, Mu-law and G.729
  • Supports simulating multiple recording servers from single instance of MAPS™
  • Scripts to automate PTT and Squelch operations on AG recording sessions
  • Recorder node automatically records voice on each session to audio files
  • Customization of parameters for multiple CWP/GRS entities to emulate an AG/GG call recording session
  • Options to easily add custom call record data properties (like Caller, Callee, Frequency) and operations (like PTT, Squelch, Call Hold)
  • Up to 200 RTSP sessions can be generated or recorded simultaneously
  • Call Record Data of each session is stored in CSV format
  • CLI/API access for seamless integration with 3rd party test tools
  • Highly flexible architecture for custom testing scenarios
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