From 7f098d0f207c327e94117599f796411a33d52e94 Mon Sep 17 00:00:00 2001 From: kpfleming Date: Tue, 4 Oct 2005 22:47:45 +0000 Subject: make timing source configuration easier to understand (issue #5356) git-svn-id: http://svn.digium.com/svn/zaptel/trunk@790 5390a7c7-147a-4af0-8ec9-7488f05a26cb --- zaptel.conf.sample | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-) diff --git a/zaptel.conf.sample b/zaptel.conf.sample index ac98114..e6cf6c5 100755 --- a/zaptel.conf.sample +++ b/zaptel.conf.sample @@ -5,12 +5,29 @@ # # # First come the span definitions, in the format -# span=,,,,[,yellow] -# -# The timing parameter determines the selection of primary, secondary, and -# so on sync sources. If this span should be considered a primary sync -# source, then give it a value of "1". For a secondary, use "2", and so on. -# To not use this as a sync source, just use "0" +# span=,,,,[,yellow] +# +# All T1/E1 spans generate a clock signal on their transmit side. The +# parameter determines whether the clock signal from the far +# end of the T1/E1 is used as the master source of clock timing. If it is, our +# own clock will synchronise to it. T1/E1's connected directly or indirectly to +# a PSTN provider (telco) should generally be the first choice to sync to. The +# PSTN will never be a slave to you. You must be a slave to it. +# +# Choose 1 to make the equipment at the far end of the E1/T1 link the preferred +# source of the master clock. Choose 2 to make it the second choice for the master +# clock, if the first choice port fails (the far end dies, a cable breaks, or +# whatever). Choose 3 to make a port the third choice, and so on. If you have, say, +# 2 ports connected to the PSTN, mark those as 1 and 2. The number used for each +# port should be different. +# +# If you choose 0, the port will never be used as a source of timing. This is +# appropriate when you know the far end should always be a slave to you. If the +# port is connected to a channel bank, for example, you should always be its +# master. Any number of ports can be marked as 0. +# +# Incorrect timing sync may cause clicks/noise in the audio, poor quality or failed +# faxes, unreliable modem operation, and is a general all round bad thing. # # The line build-out (or LBO) is an integer, from the following table: # 0: 0 db (CSU) / 0-133 feet (DSX-1) -- cgit v1.2.3