Call flow for international Roaming

Hii,
Find my answers

1. Once the Subscriber info has been sent to the visited n/w, in what other scenarios (barring another LU) is the home HLR contacted by the visted MSC/VLR?
> There are some messages (Supplementary Services) for which the VLR may initiate a contact with the HLR.
> The other thing for which i am not very sure is USSD sessions.

2. Is there some way of preventing the billing info to reach the home service provider and instead route it to a 3rd party.
> Billing info is always sent through TAP. So the home operator is not invoved till the TAP records reach it. I did not really understand your question here?

3. Does the visited HLR know, at any point of time, that a international roamer is in the network, or does the home HLR is the one point contact for any subscription info that the visited MSC/VLR may need? Incase there is any info in visited HLR, what is it & how is it updated?
>The visited HLR is not aware of the roamers profile at any point in time.

Cheers!
R…

Thanks for clarification Roameo & Scot.

In a scenario, where a subscriber is in the VPLMN, can the VPLMN network alot a local IMSI-MSISDN and map it to the original(HPLMN) IMSI-MSISDN so that all calls towards & from original IMSI can be treated as calls to/from local IMSI-MSISDN pair?

This is like a multi imsi scenario just that the simcard is not a multi imsi simcard, its the original single imsi sim, just that the mapping between 2 IMSIs is maintained in the MSC(of the VPLMN) in which the subscriber is. This should be done without involving the HPLMN.

Any thoughts?

Regards
Manul

Manul,
U cannot touch the IMSI part in the VLR but u can change the MSISDN part.
The solution you r talking about is possible if and only if the VLR has 2 records (1 dummy record) for a secondary imsi which is an exact copy of the primary record with a different IMSI/MSISDN pair.
This is a very very broad idea i can think of. If you get into specifics it becomes too complicated, since there needs to be intelligence to convert calls coming to number1 into number2, And also all map msgs would need to be transformed to update the secondary(number2) record.
Rgds

Hi,
This is what i have mentioned. You cannot touch the Imsi. But there needs to be some intelligence which modifies 2 associated records at the same time.
This again is very very broad perspective.
rgds

Well in that case why dont we Divert in to another issue….

I think this group had a great discussion.

Rgds

hello everyone;

How to connect TDMA hlr to GSM HLR

Hi Subash,

Result = E214 = CC+NDC+Remaining Digits in IMSI.Called as MGT-Mobile Global Title. This is the MGT

Dear, Isaac!
What do yoy mean under RCF abbreviation? Is it Roaming-Call Forwarding??? or???