- This topic has 15 replies, 1 voice, and was last updated 19 years, 8 months ago by Rodrigo Saucedo.
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20th May 2004 at 07:38 #38195AndrewGuest
Hi Guys,
A bit off the topic but I wonder if you guys can help me with the following: (btw I am new to CAMEL and relatively new to Mobile Comms)
1. CAMEL talks about O-CSI and T-CSI, where O-CSI is sent to the VLR of the visited MSC at LU and changes to O-CSI, and O and T_CSI are sent to the GMSC when it interrogates the HLR for routing info (GMSCs handle calls originating from the PSTN or other mobile networks, right ??)
Now why is an (V)MSC not mentioned and only a GMSC mentioned in terms of receiving the O & T-CSI?
As I understand it a call could be mobile originated and terminated and the MSC serving the MS originating the call would need to interrogate the HLR for routing info.
Does this mean that a mobile originated call to another MS in the network will not trigger TDPs set in the T-CSI??
2. I have a vague understanding of O-CSI and T-CSI !! could someone explain the difference between the two?
Kind Regards
Andrew
24th May 2004 at 19:26 #38196RoameoGuestHi,
Intresting questions.
Let me first clarify point 2 of yours.
O-CSI is used for MO-triggers from the VLR. So if A makes call to B A’s MSC/SSF uses O-CSI to decide whom to send the DP.This O-CSI is obtained during LU.
B’s GMSC first fires an SRI(routing info) to get the T-CSI.
This T-CSI is then used to fire MT-Dp’s.
I could not figure out your 1st question though. Could you please elaborate on it?
Cheers!
R….25th May 2004 at 07:33 #38197AndrewGuestHi Roameo,
Thanks for the reply. Your explanation was helpful.
I think the T-CSI issue has been clarified (actually read another previous post)
Let me explain:
T-CSI DPs are triggered in the GMSC. Now the originating MSC maybe the GMSC or it may forward a call to the GMSC where any CAMEL service for the B party is triggered.
All in all, CAMEL services are triggered if a T-CSI exists for B party.
BTW – in later phases (maybe 3 or 4) there is a concept of VT-CSI which allow terminating CAMEL services to be invoked from the VMSC of the B party.
Kind Regards
Andrew
25th May 2004 at 12:39 #38198AndrewGuestHi Roameo,
Thanks for the reply. Your explanation was helpful.
I think the T-CSI issue has been clarified (actually read another previous post)
Let me explain:
T-CSI DPs are triggered in the GMSC. Now the originating MSC maybe the GMSC or it may forward a call to the GMSC where any CAMEL service for the B party is triggered.
All in all, CAMEL services are triggered if a T-CSI exists for B party.
BTW – in later phases (maybe 3 or 4) there is a concept of VT-CSI which allow terminating CAMEL services to be invoked from the VMSC of the B party.
Kind Regards
Andrew
25th May 2004 at 13:54 #38199HariGuestHello Andrew,
According to me, if you are in the local network and u get a incoming-call the T-CSI’s are not required since, you can directly access the HLR.
Please conform the same. And also i want to know, what you got out of
(actually read another previous post)My emailId is: ajs1977@indiatimes.com
25th May 2004 at 15:40 #38200ScotGuestWhich vendor this Settings and Parameters belongs to ?
Rgds
26th May 2004 at 07:56 #38201HariGuestHello Scot,
I was not specific to any vendor settings and params.Correct me if i am wrong.
-Thanks
Hari26th May 2004 at 16:23 #38202S.VijayGuestO-CSI & T-CSI What is this ?
Rgds
2nd June 2004 at 11:52 #38203HariGuestHello Vijay,
T-CSI and O-CSI are CAMEL triggers for terminating and originating calls respectively.When MS gets into the roaming area and MAP ( Update Location ) request will be sent from VLR to HLR, the HLR other then MS info also updates VLR with O_CSI triggers.
Where as in case of terminating cals, the GMSC will be updated with the T_CSI embedded in Routing Info_ACK message.
Hope this helps…………
-Thanks
Hari3rd June 2004 at 11:17 #38204S.VijayGuestHi HARI,
What will be in OCSI Triggres…and How VPLMN MSC process such IN-Prepaid Calls ?
Do you have some Docs for this ?
Rgds
3rd June 2004 at 11:53 #38205HariGuestVijay,
According to me, OCSI will hold the kind of IN service expected by SCF, SCP may hold multiple services with different services, which required differnt triggers ( E_DP’s), so i think OCSI includes only the indication of CAMEL Support and Also service Key.I haven’t read any specs on this if any one can name the specs, it will be of great help………..
10th June 2004 at 09:41 #38206PairoteGuestHi,
I interasting this toppic.
Can you explanation about function of T-CSI in CAMEL spec.?
(It mean purpose of T-CSI)Best Begards
27th July 2004 at 06:46 #38207no-camelGuestDoes anyone know the difference between VT-CSI and T-CSI?
other than
1. VT-CSI is in phase 3
2. T-CSI is on HLR (GMSC)
3. VT-CSI is downloaded to VLR (VMSC)Other than the above, does anyone know why you would choose one over the other for Term triggering?
thanks
27th July 2004 at 08:20 #38208dennisGuestIn Camel Ph 3 funcions are almost same:
T-CSI
Possible TDPs: Terminating Attempt Authorised; $(begin$(CAMEL3$); Detection of unsuccessful call establishment (Called subscriber busy; not reachable; no answer) $(end$(CAMEL3$)
Possible DP criteria: basic service type, failure reasonVT-CSI:
Possible TDPs: Terminating Attempt Authorised; Detection of unsuccessful call establishment (Called subscriber busy; no answer)
Possible DP criteria: basic service type, failure reasonBUT in Camel Ph 2 only by VT-CSI you can detect and handle “Called subscriber busy; no answer”. In Cammel Ph 3 you have more flexibilty to decide where it is more suitable to handle IN service during MTC if it is in home network in GMSC or of it is in visited netw. of called subscriber.
To older question here-
SMS and IN – only in Camel Ph 3 and later
(SMS-CSI, SMS State models),
GPRS and IN – only in Camel Ph 3 and later (GPRS-CSI, GPRS state models)3rd August 2004 at 04:29 #38209kaniGuesthi friends,
can anyone tell me that in SSF can we use IP interface instead of E1 CAP interface. if so which CAMEL phase supports it.
with regards,
kani. -
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