Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Mission Critical Voice Quality of Experience Mouth-to-Ear Latency Measurement Method

The purpose of this software is to measure the mouth-to-ear (M2E) latency of a push-to-talk network. M2E latency characterizes the time between speech input into one communications device and its output through another. M2E latency has been identified as a key metric of quality of experience (QoE) in communications. NIST’s Public Safety Communications Research group developed this software to measure and quantify the M2E latency of Push To Talk (PTT) devices.

Obtaining Software

Code available at:

Data available at:

Paper available at

Related Software

Mission Critical Voice Quality of Experience Access Time Measurement Method

Mission Critical Voice QoE Firmware


Created January 24, 2020, Updated January 29, 2020