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GPRS Gs interface & paging

Viewing 15 posts - 31 through 45 (of 59 total)
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  • #54878
    pix
    Guest

    hi jack,

    i don’t know… Just ask your manager if this feature was bought…

    pix

    #54879
    kamal k
    Guest

    Hi Pix,
    I really didn’t understated how SGSN will page the MS which is not even known to it..? i.e.one with no GPRS facility..!

    You said that pcu will fed to BSC & bsc will page it via PCH..But how SGSN will identify that BSC..?!

    #54880
    Pix
    Guest

    Hi,

    It is the MSC that generates the Paging. In this Paging, the LAC of the MS is written.
    The SGSN knows the LAC, it knows which MFS(s) is(are) in charge of this LAC. It just forwards.

    The Gs interface means that there is a LA/RA combined update, so I’m quite sure that the SGSN won’t have a problem to correlate the LAC with the RAC. On top of that, I think that the SGSN *even without LA/RA update* knows about the Location Areas, since that is a part of the (global) RAI (RAI = LAC + RAC)

    Regards
    pix

    #54881
    kamal k
    Guest

    The SGSN rejects paging requests received from the VLR. If the SGSN has lost the Gs association (that is, the VLR address) from the MS, according to the 3GPP TS 29.018 General Packet Radio Service (GPRS); Serving GPRS Support Node (SGSN) – Visitors Location Register (VLR), Gs interface layer 3 specification (Release 5) specification, the SGSN must not accept any paging requests sent by the VLR. According to the 3GPP TS 23.060 General Packet Radio Service (GPRS); Service description – Stage 2 (Release 5), the SGSN removes the Gs association from the MS if the SGSN receives a (non-combined) RA update from the MS for which an association exists.

    #54882
    Pix
    Guest

    Hi Kamal,

    What are the conclusions you draw from those 3GPP’s extracts ? It seems to me that those are “defense” mechanisms, but perhaps I’m wrong.

    Regards
    pix

    #54883
    kamal k
    Guest

    Hi Pix,
    Yet I’m confused with your statement that how CS MS with no GPRS facility can be paged via SGSN..?!

    #54884
    Pix
    Guest

    The SGSN doesn’t check what is the state & capabilities of the MS. It is the MFS that does it.
    The MFS knows if MS is in PTM or in PIM. That is all that matters.

    I think I gave all info in my previous posts already… Read again 🙂

    regards
    pix

    #54885
    Kamal Kotecha
    Guest

    Hey Pix,

    Hi After a time,

    Our discussion was not finished on any conclusion & again I’m facing some issue with Gs..

    Any conclusion from your side..?

    Regards,
    Kamal

    #54886
    pix
    Guest

    kamal,

    well, i don’t have any issue with Gs so i didn’t work on that… but if you have issues, please share !

    old posts are 2yrs ago, i’m not going to read all that was said in the past…

    #54887
    kamal
    Guest

    Ok here is the brief:

    Having issue in paging while MS is un-reachable…While Gs is enabled..

    MSC is sending paging-request to SGSN..SGSN is triggering CS-paging message..

    But Not generating any message of Paging-reject to MSC..

    & the issue is that MSC is playing Number Does not exist Announcement…!!

    May be some issue with timers in either side…But not sure Whos responsible…!!!

    #54888
    pix
    Guest

    kamal,

    which MS are unreachable ?
    the ones in PTM especially ?
    or even the ones which are in idle mode?

    the SGSN will only be in charge of paging the MS which are in PTM. In other words, the Gs interface is used only to page MS in PTM.

    MS in Idle mode (PIM) are paged by the MSC directly, through the (Air) PCH.

    regards
    pix

    #54889
    kamal
    Guest

    GPRS attached MS…

    Doesn’t matter whether PDP is activated or not…

    They will be paged by SGSN even for CS-paging..

    Correct me if I am wrong…

    #54890
    pix
    Guest

    woaw… i said something wrong in a previous post (15th june 2010), i copied it below.

    The actual truth is different. When Gs is installed, the CS pagings :
    1/ goes from MSC to BSC (to PCH) if MS is not in PTM (= in idle mode)
    2/ goes from MSC to SGSN (to PACCH) if MS is in PTM (= in GPRS packet transfer mode)

    ********** wrong post here ********

    Pix – 15th June 2010 (17:43 GMT)

    Hi Safar,

    The rule is so simple… when you install Gs interface:
    ALL cs paging go from MSC to SGSN.
    ZERO cs paging go from MSC to BSC.

    Whatever the MS, whatever its state.
    , whatever whatever 🙂

    The thing is that it is only the PCU (=MFS in alcatel) that can process & redirect the cs pagings. It will send CS paging through PACCH, and other CS paging to the BSC (so they will later be send through PCH)
    Well, i’m sure yo understand my point 🙂

    Regards,
    pix
    *********************************

    #54891
    kamal
    Guest

    well,

    The rule is like this..

    If MS is having Gs association(SGSN attached) then paging will be done via SGSN..Whether PDP is activated or not..!!

    While,

    If MS is not SGSN attached,then it will be paged by MSC only..!!

    #54892
    Pix
    Guest

    kamal,

    yes, you are right and I was right in my very old post too 🙂
    VLR sends the CS PAGING to the SGSN if the MS is GPRS-Attached.
    Otherwise, VLR sends the paging to the MSC.

    If it went to the SGSN : The BSS will then decide if the MS is in PTM or not.
    If in PTM, Paging goes to PACCH
    If in PIM, Paging goes to PCH.

    I’m sorry about the confusion…

    Let’s recap. You’re saying that as soon as the MS is GPRS-Attached, it can’t be paged anymore ?
    Whether it is in PTM or not ?

    Basically, let’s say there are 3 MS:
    MS a is non-GPRS attached
    MS b is GPRS attached in PIM
    MS c is GPRS attached in PTM

    –> Which ones can’t get paged ?

    Second question:
    –> What kind of info are you able to collect from your SGSN ? Gs protocol traces ?

    I’m happy to help, please forgive me if I appeared aggressive somehow. I’m just being enthusiastic ! 😀 And kindly take your time to describe your problem with more details, answers my questions one by one, I’m sure we’ll get through this.

    In 3GPP specs, have you read 29.018 ?

    Regards,
    Pix

Viewing 15 posts - 31 through 45 (of 59 total)
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