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Call Setup

Viewing 11 posts - 1 through 11 (of 11 total)
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  • #38211
    Sanjeev
    Guest

    Hi,
    Can anyone confirm if the GMSC when terminating a call relies on the user status information provided in the routing response from the HLR.
    I.e. if the status information in the response to the routing query (for MSRN) says that the MS is busy or not reachable does the GMSC immediately indicate this to the calling party or does it forward the call to the VMSC?

    Please help

    SSharma

    #38212
    Scot
    Guest

    Hi SSharma,

    Other than Switched off/Implicit Detached Mode in VLR.

    MSRN Provision is irrelevent to the present Status in VLR.

    So HLR Get the MSRN from VMSC and Gives to GMSC.Then GMSC Routes the call to VMSC…Where depening upon the current situation the call may be connected / announcement/Dropped…with Cause.

    Rgds

    #38213
    Sanjeev
    Guest

    Dear Scot,
    Thanks for the reply. I really appreciate it.
    Just need some clarification:

    1. Are networks usually configured to obtain MSRN at call setup i.e. at call setup the HLR gets the MSRN from the VLR (as opposed to the VLR passing the MSRN at registration or location update)?

    2. Could you kindly explain Implicit Detached Mode?

    Do you mean to say that regardless of the ms status given in the response from the HLR to the GMSC in reponse to routing query the GMSC routes the call the the responsible VMSC unless the HLR indicates the ms is swithced off or Implicitly Detached.

    Please correct me if I misunderstood you.

    Kind Regards

    SSharma

    #38214
    Roameo
    Guest

    Hi Sanjeev,
    Find my answers below:

    1. Are networks usually configured to obtain MSRN at call setup i.e. at call setup the HLR gets the MSRN from the VLR (as opposed to the VLR passing the MSRN at registration or location update)?
    >There is no configuration as such.An MSRN is always allocated at call-setup

    2. Could you kindly explain Implicit Detached Mode?
    >Imsi Detached Mode is a case of Early Call Forwarding, where the HLR has the knowledge that the subscriber is switched of his mobile and is not active in any VLR.

    Do you mean to say that regardless of the ms status given in the response from the HLR to the GMSC in reponse to routing query the GMSC routes the call the the responsible VMSC unless the HLR indicates the ms is swithced off or Implicitly Detached.
    >Yes Scot is correct with his analysis. The MSRN is only used for routing the call to the VLR.

    Cheers!
    R….

    #38215
    Sanjeev
    Guest

    Dear Scot/Roameo

    Ok, just to confirm .. the HLR may know that the MS is not active in any VLR and would pass this info to the GMSC which may:

    1. Forward the call if CF is active for that subscriber OR
    2. Signal back to the originating exchange that the MS can not be reached (not sure how this happens though)

    Can I safely assume that in the above case an IAM is not sent to the VMSC?

    Kind Regards

    Sanjeev Sharma

    #38216
    Roameo
    Guest

    Yes u can. Unless the CF is also roaming and he is in the same VMSC. 🙂
    Cheers!
    Roameo

    #38217
    Scot
    Guest

    “Ok, just to confirm .. the HLR may know that the MS is not active in any VLR and would pass this info to the GMSC which may:

    1. Forward the call if CF is active for that subscriber OR
    2. Signal back to the originating exchange that the MS can not be reached (not sure how this happens though)

    Can I safely assume that in the above case an IAM is not sent to the VMSC? ”

    With Reference to above :-

    1.Yes an anothe Callsetup with IAM will bestarted.
    2.GMSC Gtes the ABSENT Inf in “ROUTING ENQUIRY Response ” so it drops the call to announcement.

    Rgds

    #38218
    Sanjeev
    Guest

    Thanks Scot 🙂

    Regards

    SSharma

    #38219
    Sanjeev
    Guest

    Hi Guys,
    Sorry me with more questions !!

    What happens if a call needs to be forwarded in the GMSC. What I mean is that the GMSC does not have the subcriber info resident in its VLR (unless of course the forwarding sub is roaming in its area)??

    Any thoughts?

    Kind Regards

    SSharma

    #38220
    S.Vijay
    Guest

    Sanjeev CF at what Condition ?

    Rgds

    #38221
    Sanjeev
    Guest

    Hi,

    Sorry for a late response.

    I guess the call forwarding at the GMSC would be under Call Forwarding Unconditional (the others as I understand .. please correct if i am wrong .. would be at the VMSC??).

    In which case in forwarding to the FTN (which is a MS) does it not need to know subscription info for that number?? And if it does where is this info obtained from (If the FTN was roaming in the GMSC area it would have this info in it’s VLR)

    Kind Regards

    SSharma

Viewing 11 posts - 1 through 11 (of 11 total)
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