[asterisk-bugs] [Asterisk 0005356]: Getting the clocking right for E1 and T1 lines

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=5356 
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Reported By:                steveu
Assigned To:                kpfleming
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Project:                    Asterisk
Issue ID:                   5356
Category:                   Core/General
Reproducibility:            always
Severity:                   feature
Priority:                   normal
Status:                     closed
Asterisk Version:           I did not set the version :( 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Disclaimer on File?:        Yes 
Request Review:              
Resolution:                 fixed
Fixed in Version:           
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Date Submitted:             10-02-2005 03:42 CDT
Last Modified:              06-07-2008 11:05 CDT
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Summary:                    Getting the clocking right for E1 and T1 lines
Description: 
If the wording about setting clock sources in zaptel.conf.sample is changed
to that below I think I will have a lot less support issues with spandsp.
:-) This was discussed some time ago on the mailing list, but it looks like
CVS was never changed. I think the *majority* of users currently have their
clock sources set incorrectly, and the current wording makes the adamant
they are right.

# span=<span num>,<timing source>,<line build out
(LBO)>,<framing>,<coding>[,yellow]
# # All T1/E1 spans generate a clock signal on their transmit side. The   
      # <timing source> 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.
#
# Chose 1 to make the equipment at the far end of the E1/T1 link the
preferred
# source of the master clock. Chose 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). Chose 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 awlways 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.

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---------------------------------------------------------------------- 
 svnbot - 06-07-08 11:05  
---------------------------------------------------------------------- 
Repository: dahdi
Revision: 790

U   trunk/zaptel.conf.sample

------------------------------------------------------------------------
r790 | kpfleming | 2008-06-07 11:05:08 -0500 (Sat, 07 Jun 2008) | 2 lines

make timing source configuration easier to understand (issue
http://bugs.digium.com/view.php?id=5356)

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http://svn.digium.com/view/dahdi?view=rev&revision=790 

Issue History 
Date Modified   Username       Field                    Change               
====================================================================== 
06-07-08 11:05  svnbot         Checkin                                      
06-07-08 11:05  svnbot         Note Added: 0088072                          
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