...large enterprise there will be varying requirements for voicequality, and this should be considered when investing in converged solutions. For some internal communication, lower voicequality can be tolerated, given that in many cases staff use...
http://www.computerweekly.com/Articles/2002/10/17/190317/voip-still-on-hold.htm
...partners with Avaya to provide voicequality monitoring to Avaya customers...Avaya Inc to provide PROGNOSIS voicequality monitoring solutions to Avaya...to ensure the highest level of voicequality for Avaya customers.” “This...
http://www.prognosis.com/page__2667.aspx