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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Usually if you have one long distance voice PRI from AT&T
and another voice PRI for local calls with Verizon on same VWIC2-2MFT-T1 card
you have timing issues due to the single PLL design. Best bet would be to separate
into two VWIC2-1MFT-T1 cards if in doubt. If both PRIs were from same carrier
you are less likely to have different timing. <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>Derick Winkworth<br>
<b>Sent:</b> Monday, August 25, 2008 11:40 AM<br>
<b>To:</b> cisco-voip@puck.nether.net<br>
<b>Subject:</b> Re: [cisco-voip] network-clock-participate???<o:p></o:p></span></p>
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<p>In telco-land, there is the idea that all network switches are synchronized
to the same clock. This is achieved by planning how a clock is
distributed through your network. The idea is that there is one clock
device in a network switch, called a PLL (phase-lock loop). The
PLL will receive/recover the master clock on one of its bearer ports, or
on a dedicated clock port called a BITS port.<o:p></o:p></p>
<p> <o:p></o:p></p>
<p>All other ports on that switch/device will be timed using this master clock.<o:p></o:p></p>
<p> <o:p></o:p></p>
<p>Cisco's ISRs were built using this model. There is one PLL on the
motherboard, called the network-clock. Modules on your router may
participate in this clocking scheme or not. Some have to, because they
don't have their own PLLs/clocks on-board. When you need/want a module to
participate in the network clock, you use the network-clock-select
command. You select the master clock with the network-clock-select
command. You can choose multiple master clocks and order them by
priority. Only one is active at a time.<o:p></o:p></p>
<p> <o:p></o:p></p>
<p>The implication here is that if you connect to multiple carriers (and thus
multiple clock domains), you may/will end up with clock slips on one of the
ports. Otherwise, you would set the telco port as the master clock and
then time the rest of your private ports off of this. You may need
to do this if you want the ISR to do TDM switching, for instance.<o:p></o:p></p>
<p> <o:p></o:p></p>
<p> <o:p></o:p></p>
<p> <o:p></o:p></p>
<p> <o:p></o:p></p>
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<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>-----
Original Message ----<br>
From: "Carter, Bill" <bcarter@sentinel.com><br>
To: john edwards <voicenerd@googlemail.com>; cisco-voip@puck.nether.net<br>
Sent: Sunday, August 24, 2008 7:45:32 PM<br>
Subject: Re: [cisco-voip] network-clock-participate???<br>
<br>
<a
href="http://www.cisco.com/en/US/docs/ios/voice/voiceport/configuration/guide/"
target="_blank">http://www.cisco.com/en/US/docs/ios/voice/voiceport/configuration/guide/</a><br>
vp_cfg_digital_vps_ps6441_TSD_Products_Configuration_Guide_Chapter.html#<br>
wp1009559<br>
<br>
"The network-clock-participate command allows the router to use the<br>
clock from the line via the specified slot/WIC/AIM and synchronize the<br>
onboard clock to the same reference."<br>
<br>
<br>
<br>
<br>
-----Original Message-----<br>
From: <a href="mailto:cisco-voip-bounces@puck.nether.net">cisco-voip-bounces@puck.nether.net</a><br>
[mailto:<a href="mailto:cisco-voip-bounces@puck.nether.net">cisco-voip-bounces@puck.nether.net</a>]
On Behalf Of john edwards<br>
Sent: Sunday, August 24, 2008 5:53 PM<br>
To: <a href="mailto:cisco-voip@puck.nether.net">cisco-voip@puck.nether.net</a><br>
Subject: [cisco-voip] network-clock-participate???<br>
<br>
Hi everyone,<br>
<br>
I wonder if anyone knows where I can find a thorough explanation of<br>
the 'network-clock-participate' and 'network-clock-select' commands?<br>
<br>
I have trawled through multiple references, but I am still confused :-(<br>
<br>
Thanks very much in advance.<br>
<br>
Voicenerd<br>
_______________________________________________<br>
cisco-voip mailing list<br>
<a href="mailto:cisco-voip@puck.nether.net">cisco-voip@puck.nether.net</a><br>
<a href="https://puck.nether.net/mailman/listinfo/cisco-voip" target="_blank">https://puck.nether.net/mailman/listinfo/cisco-voip</a><br>
_______________________________________________<br>
cisco-voip mailing list<br>
<a href="mailto:cisco-voip@puck.nether.net">cisco-voip@puck.nether.net</a><br>
<a href="https://puck.nether.net/mailman/listinfo/cisco-voip" target="_blank">https://puck.nether.net/mailman/listinfo/cisco-voip</a><o:p></o:p></span></p>
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