Avaya S8700 Maintenance Manual page 46

Maintenance Architecture
ERL and SFRL Talking State
Echo-Return Loss (ERL) and Single-Frequency Return Loss (SFRL) performance
are usually dominated by termination and/or loop input impedances. The system
provides an acceptable level of echo performance if the ERL and SFRL are met,
as follows:.
Station-to-station
Station to 4-wire trunk connection
Station to 2-wire trunk connection
4-wire to 4-wire trunk connection
Peak Noise Level
Analog to analog — 20 dBrnC (decibels above reference noise with
C-filter)
Analog to digital — 19 dBrnC
Digital to analog — 13 dBrnC
Echo Path Delay
Analog port to analog port — < 3 ms
Digital interface port to digital interface port — < 2 ms
1-22 Issue 1 May 2002
ERL should meet or exceed 18 dB SFRL
should meet or exceed 12 dB
ERL should meet or exceed 24 dB SFRL
should meet or exceed 14 dB
ERL should meet or exceed 18 dB SFRL
should meet or exceed 12 dB
ERL should meet or exceed 27 dB SFRL
should meet or exceed 20 dB
555-233-143