This paper proposes a theoretical model and an ITU-T H.323 compliant empirical measurement method for the acoustic round trip delay (ARTD) of a voice over Internet protocol (VoIP) conference. The empirical measurement method is able to compute the complete acoustic round trip delay that the user perceives. The acoustic round trip delay is experimentally measured by slicing the real-time signal path and inserting test hooks on the Carleton University VoIP platform. Current VoIP systems cannot measure the acoustic round trip delay. An acoustic domain verification test is used to check the ARTD empirical measurements for accuracy.
2nd IEEE Workshop on Multimedia Signal Processing, MMSP 1998
Department of Systems and Computer Engineering

Yensen, T. (T.), Parperis, M. (M.), Lambadaris, I, & Goubran, R. (1998). Determining acoustic round trip delay for VoIP conferences. In 1998 IEEE 2nd Workshop on Multimedia Signal Processing (pp. 161–166). doi:10.1109/MMSP.1998.738929