Transmission planning aspects of echo cancellers Amendment 1: New Appendix III Guidance for using echo cancellers to prevent low-level echo Study Group 12
Echo control has proven to be a major challenge inefforts to deliver PSTN-equivalent voice quality in the VoIP environment. The primary echo problem encountered early in the VoIP evolution is referred to as “initial echo” where the customer hears echo on the first few syllables they speak at the beginning of a call. Fortunately, this problem has been significantly reduced by the introduction of network echo cancellers that have improved (i.e., faster) convergence speeds.