CER, RTT requirement between PUB and SUB

Unanswered Question
Mar 21st, 2009
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I have two data centers and will be installed CUCM_PUB and CUCM_SUB in each location. and I want to install CER servers in each location as below combination but cannot find out CER requirement from CCO.

-data center1, CUCM_PUB, CER_PUB

-data center2, CUCM_SUB, CER_SUB


-can I install CER servers with the above combination?

-what is CER RTT (or something else) requirement between CER Publisher and Subscriber?

-CUCM RTT requirement is 80ms (after version 6.1). Is CER requirement belonging to CUCM?

***the CER subscriber requirement as per CER admin guide,

'Consider installing the standby server in a physically separate location from the primary server, and on a separate subnet not separated by a WAN link'


Advise plesae,


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gogasca Sun, 03/22/2009 - 16:30
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Hi John,

There can be up to 40 msec RTT between a CUCM server and a CER server in a CoW


This implies that there will be no more than 40 msec RTT between

CER publisher and CER subscriber as well.

If I remember correctly, the minimum bandwidth between CER publisher and

subscriber was the equivalent of a T1.

I'm not aware of any maximum delay or minimum bandwidth between CER servers in

different server groups.


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