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If the primitive at TCAP is END, does it mean conversation finished?

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hoangsonk49
If the primitive at TCAP is END, does it mean conversation finished?

Hi all, I'm analyzing SS7 at TCAP and CAMEL layer. As I know, in TCAP, we have primitives: Begin, Continue, and End. Corresponding to them are some kinds of mess in CAMEL layer: InitDP (Begin) , Request Report, AppCharging (Continue), ...I use wireshark to capture packet to decode in order to know the flow of Busy Call and Normal Call (Connect-Talking-End Call). But I wonder
1. if we see the End primitive at TCAP, does it mean the conversation finished ? (I mean from user 's point, not system 's point, of course the system needs to do something but I just take care of when user hang up).

2. i check many Normal Call (by decoding Cause indicator = normal call clearing and eventTypeBCSM: oDisconnect (9) ) but I saw: sometime, the mess of CAMEL corresponding to End primitive of TCAP is "Continue" : "local: continue (31)", but sometime: "ReleaseCallArg: allCallSegments (0)". So, when TCAP is END, what is the difference of Camel mess "Continue" and "Release call". For Busy call and Normal call, what is the Camel mess corresponding to TCAP END? Continue or Release call?

Thanks.

mlntdrv
mlntdrv's picture
Hi hoangsonk49,

Hi hoangsonk49,

"1. if we see the End primitive at TCAP, does it mean the conversation finished ?" - No, this means that only the CAP dialogue is finished.

2. When CAP.CUE is received through TC_End, this means that the call is allowed and no further control is needed, thus the SCP closes the CAP dialogue by using TC_End. Receiving CAP.RC in TC_End, I think it's pretty obvious, release the call and no further control is needed.

Cheers!

hoangsonk49
Hi hoangsonk49,

Oh i see, thank you very much :-)