I am confused with the calculations for SCCP Call Control Traffic in the CUCM v8 SRND.
An equation of Bandwidth (bps) = 265 X (Number of IP phones and gateways in the branch) is provided with the assumption implied of 10 calls per hour per phone, this equation this matches the table provided, which for example states 100 phones using non-encrypted SCCP requires 27kbps for signalling.
The confusion comes when I look at the advanced formulas which allow you to specify a calls per hour (CH) per phone ratio. The equation provided is Bandwidth (bps) = (53 + 21 X CH) X (Number of IP phones and gateways in the branch), if we use the CH ratio of 10 (as per the above formula) I would assume this should mean (53+21 X 10) X (No of Phones) however this would suggest 74k would be required for 100 phones, how can the two formulas vary so much?
Also can someone confirm the different requirements for call signalling between the CUCM the phone is actively registered too compared with the Standby CUCMs.
If anyone has a link to the relevant documents with the above formulas or can explain the method behind the SRND ones it is appreciated.
Well, not really as this is simple algebraic equation, multiplication is done first with no need for parenthesis :-)
You don't need to worry about standby servers as all they receive from the phone is the keepalive every 30 seconds which is negligible, 4 bytes every 30 seconds even for thousands of phones does not add up to a lot.
SIP traces provide key information in troubleshooting SIP Trunks, SIP
endpoints and other SIP related issues. Even though these traces are in
clear text, these texts can be gibberish unless you understand fully
what they mean. This document attempts to br...
Please find the attached HTML document, download and open it on your PC.
This provides an easy to use form where you simply answer a few
questions and it will render the proper jabber-config.xml file for you
to copy/paste. There is built in logic to verif...
CUCM Database Replication is an area in which Cisco customers and
partners have asked for more in-depth training in being able to properly
assess a replication problem and potentially resolve an issue without
involving TAC. This document discusses the bas...