- This topic has 42 replies, 1 voice, and was last updated 2 years, 6 months ago by Wallis Dudhnath.
29th March 2004 at 12:48 #37807HariGuest
I want to know the use of IN in GSM. I mean, by using IN how GSM will support new features and supporting these features in visiting network. With out IN how these services where supported in GSM, iff they were supported.
Any call flows which will help me know IN and GSM, will be of great help.
Hari29th March 2004 at 13:26 #37808waleedGuest
are you asking about billing in gsm ?thats what are you meaning by IN?31st March 2004 at 09:00 #37809PankajGuest
IN offers whole range of new features and services and various vendors support different type of services and perpaid being the most used service. Othe then pre-paid there are other services e.g. Virtula private networks (VPN) free phone, one number , premium calling etc, that are not feasible without using Intelligent Networks. You can get hold of the standards that shall provide you all the call flows and other details.3rd April 2004 at 14:13 #37810ScotGuest
By implementing IN in GSM Networks you can create various services as mentined by Mr.Pankaj and you can creat some new and Charging can be done differently.
More are less IN-Helps you to utilise the network resources effectively.Where there are some IN Like systems but they require lot of resources and creation of new services will be hard,more complex.
Nowadays for IN become like a common standard with common Application Protocal – CAMEL which allows you to provide the custom made applications for your Roaming Subscribers.
Prepaid Roaming another result.
Scot8th April 2004 at 09:53 #37811HariGuest
Thanks for your reply.
Basically without IN (which means CAMEL in GSM and INAP in fixed n/w) how we used to support pre-paid calls in visiting network?.
According to what i have understood is in CAMEL we look into the T_CSI Or O_CSI flag and decide on using CAMEL for terminating or originating calls.
( In IN these T_CSI and O_CSI work like trigger points for pre-paid user calls, if i am not wrong). According to me, when first time pre-paid user is detected the “MAP messages which flow between VLR and HLR for getting the user related information) will basically hold these flags. So, VLR maintains these flags!!!!!. Again not sure.
And when GMSC or VMSC decide to apply CAMEL for orig/term call the request (INIT-DP) will be sent to gsmSCF (a process running on HLR) from gsmSSF ( a process running on MSC).
The point to note is, the VMSC’s gsmSSF will interact with (gsmSSF)HLR of the pre-paid user home network. Please correct me if i am not wrong.
And then gsmSCF will reply with Request Reports (ApplyCharging,EventReportBCSM,Connect… etc) and when the call gets disconnected the Reports generated @ VMSC will be reported to HLR, which update the billing system.
How pre-paid was support without CAMEL is still a question?. One possible answer can be VMSC maintains the CDR’s and we collect manually or using X.25 link from VMSC and update these CDR’s on HLR. But the problem is if user makes a call whose cost is more then the present available balance in his/her account then above said will not work.
And i have one more point which requires your support to know better, how does OSS (Operator Specific Services) will be supported using CAMEL?.
I tried to understand this point, and have the following idea. CAMEL supports play-announcement, now to play announcement ( which is specific to an operator), the VMSC can use gsmSRF of per-paid user’s home network.
I mean, the gsmSCF which requests VMSC (gsmSSF) to handle play-announcement will refer gsmSRF of pre-paid’s home network.
But i am not sure. Please clarify my understandings.
Hari8th April 2004 at 09:57 #37812HariGuest
I want to know the call flows traces if any are available, please do send them to me.
my e-mailId is: firstname.lastname@example.org April 2004 at 18:21 #37813ScotGuest
* CAMEL is the best solution to support Prepaid Raoming.Or we have to go for proper IN-Data Defintions to co operate with Other PLMNs.That is not possible with all the vendors.
* There are differnt IN Keys,which can be used to Invoke the IN Services.By proper defintions for each triggering you can make differnt setup of call handling for differnt keys.
* HLR Just provides a copy of Subscriber data to VLR.But SSF/MSC is responsible for acting according to the triggering table.
* gsmSCF Runs as differnt Functionality.It is not a integrated functionality of HLR but can be implemented in same HW Platform.it can work as co working application or standalone node.
* gsmSSF always interacts with gsmSCF/SCP while processing a call…not with HLR.Since gsmSSF is implemented in a MSC Node…depending upon the setup the MSC Can Initiate a Authrization process.But it depends upon the MSC Functionality not in SSF.
*During a call the SCP & SSF are always in communication with eachother.So the billing is like ONLINE Billinbg for PREPAID Subscribers.No need to go for POST Processing of CDRs.But MSC includes this call datas in its CDRs.Which can be used or not used for other purposes.Charging will be purely controlled by SCF incase the implementation is for PREPAID.
* PREPAID Roaming is avilable without CAMEL.But in this case the above mentioned CDRs from MSC willl be used.But the charging will take place 5/6 times in a day.And it depends upon the CDR reception from other VPLMNs.Then they will apply OG/IC-Barring if they find somebody without money.
*OSS in CAML-No Idea
*For announcement there should be Close cooperation between SSF & SCF so it is not possible in case of a Country to Country Roaming.
* There are some other methodes like USSD and Call back features…etc….
Hope this clarifies a bit 4 u and Call Flow Traces sorry..I cant get…since there are 16 Links between our SSF and SCF…I cannot do tracing for this.
Our Analyzer-Nethawk is capable of Two Links only.
Scot16th April 2004 at 08:55 #37814WALEEDGuest
DEAR ALL sorry for miss understanding,about IN..19th April 2004 at 10:18 #37815HariGuest
Thanks for your valuable inputs.
The USSD callback solution which you are refering is about home USSD server triggering two calls and cross-connecting both the calls if i am not wrong.
Hari19th April 2004 at 11:02 #37816ScotGuest
Yes Hari I was refering the same.
This is totally controlled by HPLMN.
Scot20th May 2004 at 11:10 #37817AndrewGuest
Very informative discussion. Thanks
Does anyone have an idea as to which CAMEL phase (i.e. Phase 1, 2 or 3) is currently implemented within mobile operator’s networks?
Does the fact that an operator has GPRS, have anything to do with what CAMEL phase they are at??
Just going back to the discussion, in terms of CAMEL I think the whole idea is to enable an operator to offer OSS (Operator Specific Services) that are avilable while roaming (of course the visited netwrok needs o be CAMEL aware). This is done by trnasferring the CAMEL Subscription Information (CSI) to the VLR of the VMSC at registration of location update or when CSI changes.
One of things the CSI has is the address of the SCF in the HPLMN and the VMSC can query the SCF in the HPLMN in case it comes accross any armed triggers.
Andrew25th May 2004 at 09:00 #37818HariGuest
As of what i know CAMEL phase-2 the present need.
Hari25th May 2004 at 09:50 #37819AndrewGuest
Thanks Hari for the response and the info. Appreciate it.25th May 2004 at 12:25 #37820AndrewGuest
Could someone confirm that Phase 2 of CAMEL is needed to provide real time Pre Paid for voice.
Any ideas if it can manage SMS? (or have totally lost the plot??) 🙂
Andrew25th May 2004 at 16:33 #37821Jack SparrowGuest
Can you explain a bit about using USSD and connecting two Calls ?
MAP-Process Unstructured SS Request.