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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I have this running on about 90 28XX routers in the field. Sprint
MPLS circuits on the data side and Verizon or AT&T PRIs. You have to set
network clock select to the PRI for it to come up, therefore the data circuit
slips. Out of the 90 sites, only 2 have required new VWICs because of errors.
The rest tolerate the slips. I see as low as 15 and as many as 90 slip seconds
on the data circuits. 40 or 50 seems to be the limit for me, your mileage may
vary.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Timothy Estes<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Data Network Operations Engineer<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>ACS / Spherion<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Ft. Lauderdale FL<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
cisco-voip-bounces@puck.nether.net [mailto:cisco-voip-bounces@puck.nether.net] <b>On
Behalf Of </b>Ed Leatherman<br>
<b>Sent:</b> Wednesday, February 04, 2009 9:38 AM<br>
<b>To:</b> cisco-voip@puck.nether.net<br>
<b>Subject:</b> [cisco-voip] Question about T1 clocking<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Hi folks,<br>
<br>
Been thru a number of threads and also "configuring digital voice
ports" out on <a href="http://cisco.com">cisco.com</a>.. I think i
understand what I need to know from it but for one question.<br>
<br>
I've got a regional campus that wants to connect a long distance (sprint I
think) T1 to an existing IOS gateway that has a VWIC2-2MFT-T1 with a free port.
The other port is a PRI to their local service provider. i've told them that I
believe this will cause clocking issues since they are from different carriers
and would not recommend it.<br>
<br>
My other thought was to add another VWIC to this router so that the long
distance T1 has a seperate PLL, but then I started reading about the
network-clock-select - even if I did this, the clocks running the DSP's would
still be synched to one particular line clock and i'd still likely get slips,
is this this true? Is my only option to get a seperate router for this
application if I want to avoid having clocking problems?<br>
<br>
Thanks in advance!<br clear=all>
<br>
-- <br>
Ed Leatherman<br>
Assistant Director, Voice Services<br>
West Virginia University<br>
Telecommunications and Network Operations<o:p></o:p></p>
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