<div class="gmail_quote"><div>There are no explicit constraints in the SRND but it does mention from here <a href="http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/8x/models.html#wp1043663">http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/8x/models.html#wp1043663</a>:<br>
<br><span class="content"><h3 class="p_H_Head2">Best Practices for the Centralized Call Processing Model
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<a name="wp1043664"></a><p class="pB1_Body1">
Follow these guidelines and best practices when implementing multisite centralized call processing deployments:
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•<img src="http://www.cisco.com/en/US/i/templates/blank.gif" alt="" width="19" border="0" height="2">Minimize delay between Unified CM and remote locations to reduce voice cut-through delays (also known as clipping).
</p></span><br>Keepalive timers between CUCM and an IP Phone are in the orders of seconds, so it shouldn’t be an issue and hence there is no specific requirement about latency.<br><br>Take into account that in a previous life we implemented CUCM over a satellite connection and apart from delay for dialtone, etc, it worked on the whole, well. <br>
<br> </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div link="blue" vlink="purple" lang="EN-GB">
<div><div><p class="MsoNormal"><font face="Tahoma" size="2"><span style="font-size: 10pt; font-family: Tahoma;" lang="EN-US"><b><span style="font-weight: bold;">Sent:</span></b> 20 August 2010 21:15<br>
<b><span style="font-weight: bold;">To:</span></b> <a href="mailto:cisco-voip@puck.nether.net" target="_blank">cisco-voip@puck.nether.net</a><br>
<b><span style="font-weight: bold;">Subject:</span></b> [cisco-voip] Call Control
/ Phone Registration Distance</span></font><font face="Times New Roman" size="3"><span style="font-size: 12pt; font-family: "Times New Roman";" lang="EN-US"></span></font></p><b><font face="Tahoma" size="2"><span style="font-size: 10pt; font-family: Tahoma; font-weight: bold;" lang="EN-US">From:</span></font></b>
<a href="mailto:cisco-voip-bounces@puck.nether.net" target="_blank">cisco-voip-bounces@puck.nether.net</a> [mailto:<a href="mailto:cisco-voip-bounces@puck.nether.net" target="_blank">cisco-voip-bounces@puck.nether.net</a>] <b><span style="font-weight: bold;">On Behalf Of </span></b>H, Tim<br>
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<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;"> </span></font></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US">All,</span></font></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US"> </span></font></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US">Does Cisco give a limitation on Distance/Latency on how far away from a
CUCM cluster you can be before they don’t support phone registration/call
control?</span></font></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US"> </span></font></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US">I haven’t been able to find documentation, but if someone knows where
to find that, it would be very helpful to me.</span></font></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US"> </span></font></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US">Thanks,</span></font></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US"> </span></font></p>
<p class="MsoNormal"><b><font color="#1f497d" face="Calibri" size="2"><span style="font-size: 11pt; color: rgb(31, 73, 125); font-weight: bold;" lang="EN-US">Tim </span></font></b><i><font color="#1f497d" face="Arial" size="1"><span style="font-size: 8pt; font-family: Arial; color: rgb(31, 73, 125); font-style: italic;" lang="EN-US"></span></font></i></p>
<p class="MsoNormal"><font face="Calibri" size="2"><span style="font-size: 11pt;" lang="EN-US"> </span></font></p>
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