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cm trace explaination and description

dear sir,

Plesae let me know how we explain and read the cm trace? where's the line and point that we should concentrate on the cm trace? Please advise. Hereby attached the cm trace.


Re: cm trace explaination and description

AVVID traces are extremely detailed as well as cryptic in alot of cases.

we won't be able to tell you all you need to know about reading trace files but i'll tell you what you a couple of basics to get started and where to find most of your answers....

example trace from your file:

07/21/2006 13:15:39.763 CCM|StationInit: (0000188) TimeDateReq.|<:PENANG-CCM4-CLUSTER><:><:2>

07/21/2006 13:15:39.763 CCM|StationD: (0000188) DefineTimeDate timeDateInfo=7/21/2006 13:15:39,5 systemTime=1153458939.|<:PENANG-CCM4-CLUSTER>

these lines show the date/time, traceType (CCM) and Process (StationInit, etc...) along with alot of other information that details phone ip, ccm ip, clusterID....more

StationD: - is a message from callManager to an IP phone

StationInit: - is a message from an IP phone to callManager

DigitAnalysis: - is callManager doing digit matching on the digits entered for making a call against the dialPlan

you may notice that the IP Phone does nothing unless callManager tells it to.

typical phone call includes:

1) ip phone goes off-hook. sends a StationInit message to callManager that it is off-hook.

2) callManager sends a StationD message to the phone to play DialTone.

3) the ip phone begins to play dialTone until a button is pressed or timesout to a busySignal.

4) upon user pressing a button, ip phone sends a StationInit message to callManger with the button pressed.

5) callManger sends a StationD message to the phone to stop playing dialTone.

6) callManager performs a digit analysis to see if the dialPlan has an entry for the digit(s) entered. this continues until callManager finds a dialPlan match and forwards the call to the appropriate endpoint or finds no match and sends a StationD message to the ip phone to play FastBusy tone.

7) once callManager finds a match it performs call Setup with the two endpoints involved. (usually an ip phone & gateway or ip phone & ip phone.) these messages include OpenReceiveChannel and startMediaTransmission, among many others depending on the call leg.

8) once you see startMediaTransmission from both endpoints, callManager leaves the conversation and the two endpoints communicate directly with each other. (startMediaTransmission means that all call setup is completed and the devices can begin sending RTP streams to each other)

there are many more processes involved among possibly many different endpoints and procedures. cannot tell you all here.

an excellent book to learn as much as possible is Cisco Press: 'Troubleshooting Cisco IP Telephony".

there are also ways to know which messages belong to which call and/or callLeg. these are TCP handles and callIDs uses in the messages which are explained in the book mentioned above as well.