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Zoltes Voice, Fax and Data Modem Traffic Generator (VFD) is an end-to-end testing tool for PSTN enabled devices using generic call flows and media streaming features across analog and TDM telephony interfaces with Quality of Voice and Quality of Fax.


  • Multi-Test Agent control from the same controller interface
  • Tones, Voice, Fax and Data Modem traffic mix on any channel
  • Execution control
    • Test Automation and via TCL
    • Flexible dial plan support
    • Conditional If and Loop statements in Test Script
    • Rerun test if failed, stop after failure, continue after failure
  • Test Statistics
    • Summary
    • Detailed
  • Test Results
    • Thresholds, Error Codes per failure
    • List of error codes with summary description
  • Ability to load the PCM recording files in Adobe Audition (CoolEdit) or similar analysis tool
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Zoltes voice, fax and data modem end-to-end testing


  • All-in-one tones, voice, fax and data modem traffic generator for analog and TDM networks
  • Assess media streaming transmissions with Quality of Voice and Quality of Fax analyses
  • Originating/ terminating PCM recordings available for further in-depth analysis
  • Flawless integration with Zoltes V.34 Fax Analyzer.



3300 N. Main Street, Suite D
Anderson, SC 29621-4128
Phone: +1 (864) 642-1571

Copyright Zoltes, Inc. 2019. All rights reserved.