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26th May 2004 at 16:20 #38170S.VijayGuest
When the call reaches VMSC it is its responsibility to Process Further.May Drop or Provide Announcement.
If it Drops defnly it will be for some genuine case.At this stage GMSC Can act according to REL Caus and Provide ANNOUNCEMENT if they want to.
What do you think Guys ?27th May 2004 at 16:00 #38171Ashish GoelGuest
Your reason may be correct. Let us consider the scenario as :
After the RBT is received at A side there can be three cases:
1) Call is released (whatever is the reason) and an REL message is sent to a side.
2) Call is answered and an ANM is sent to A side.
3) The call is not released but is routed to ann.
The first two cases are simple to understand. But in the third case we see that before the announcement the rbt has ended and that means some som evnt has occurred at B side and it should send an appropriate message, but we get an announcement. So in this case i think some message should be received by A side ( in my opinion ANM). i want to know exactly what message is received and what are the contents if i am not going wrong.
I have analysed it on the SIEMENS switch by starting a dest report and activating the signalling trace on it.
In the trace the reason for release was ” Call Abondoned after first digit” and in the DEST report the call was put under CCS unanswered which means that this call was unanswered.
Your suggestions on this will be very helpful.
Ashish28th May 2004 at 10:14 #38172S.VijayGuest
Anns 3 : The announcement played between ACM and REL.
There will be RELEASE CAUSE in ISUP-REL Which may explain why the call released.
Means it may relate somehow to the EVENT whcih relaesed the call.
REL May be sent from either direction depending upon Release Event.
As per my observation :-
No Response ANNOUNCEMENT – A Exchange Releases.
Detached Mode ANNS – B Exchange Releases.
Messages : IAM–>
ACM29th May 2004 at 07:42 #38173hi vijayGuest
thanks for the reply. RBT is ring back tone. The REL message send the release cause as Unanswered call as per your comments. But is there any message in between REL and ACM whcihh tells the A side that the call is being routed to ann. and it should end the RBT.
Also can you please tell me what is the exact purpose and diff uses of call progressing message ( CPG ) in c-7 and in an E-1 connectivity how the status of trunks is maintained in CCS-7 n/w.
Ashish Goel29th May 2004 at 11:00 #38174SanjeevGuest
Here are my 2 cents on the issue (please correct me if I am wrong) .. I will try discussing it in context of a PLMN
I think once VMSC sends release message to GMSC with the casue being no answer, then the GMSC must connect to IVR and would send an ANM to VMSCA so that VMSCA tells A party that it connects to a voice channel .. otherwise party A will not be able to listen to announcement.
What do u guys think??
Sanjeev Sharma29th May 2004 at 13:12 #38175S.VijayGuest
Can you give me the REL-Cause Value for ” Call Abondoned after first digit” ?
I dont know much abt SIEMENS So I cannot explain abt CCS-REPORT.
Rgds29th May 2004 at 14:01 #38176Ashish GoelGuest
The rel reason Call Aban after first digit actuallt tell us that the call was flowing normally but was released due to system beace of any reason here we can say that it was routed to ann.
I have discussed thai thing and arrived at the following result:
The call is routed to ann after ending the ring back tone and it mentions the release cause as an unanswered call(REL is sent after the ann is played).
i have a doubt that whether the A side receives any message between the events ending the ring back tone and giving the ann.
In siemens an incept is created for the ann which sends the rel cause. Here it sends the release cause as unanswered call.
Do share your views if i am wrong and tell me if any message is sent as i have discussed.
Ashish29th May 2004 at 15:25 #38177S.VijayGuest
There is some Problem in this Discussion Board.My messages are not getting added properly.
Between ACM and REL Messages there is a possibility of CPG Message
That is only comes when there is paging is going and Still No response.
CPG Message is adds more info to ACM…that it informs that the Call is In Progress + Prsnt Stastus of the Subscriber.
There wont be any CIP Message for DETACHED CONDITION.
CKT Status maintianed for responsible SW Units which Control the Route and CKTs.29th May 2004 at 17:37 #38178S.VijayGuest
Hi Sanjeev Sharma,
While providing Announcement , GMSC Wont connect to IVR it will connect to (G)MSC Announcement System.This is as per the outcome of the MT Call Process Result.
For announcement it wont send any IAM.or any other Message.Since the incoming call already SEIZED a device with IAM it will play the announcement on that Device.
If you do Tracing with Analyzer and TAP that Circuit you can realise this.29th May 2004 at 17:41 #38179S.VijayGuest
Between ACM and REL ther is apossibility of CPG in case if the call is No Response Kind.Announcement played between CPG and REL in this case on the same circuit which was seized by IAM.
In case if the MT Call to DETACHED MS Then there wont be any message between ACM and REL.And the announcement is played between these two.
** Lets go step by step….Dont mix other things…If we have doubt we will clear here itself.
Rgds29th May 2008 at 03:42 #38180rizzaGuest
im also confused with regards to which party sends an announcement.. but based from the trace i gathered, If B-party releases the call, the originating point code will be the one to give an announcement..
i still have one question, what is the appropriate release cause for call drop?
hope you could help me with this.
thanks a lot!19th October 2011 at 10:07 #38181Zelagio GomesGuest
some seconds I heard noise in the line like if someone was at the other side of the line. Then the call has been established and the phone has been ringing but no one answered.why the B number dont recieve any incoming call ?