FR2831381A1 - Mobile phone packet mode location service procedure can continue after cell change - Google Patents

Abstract

A mobile phone packet mode location service procedure continues execution in the base station (BSS) if possible during cell changes using data including new cell identification and Network Service Entity sent from the Serving GPRS Support Node (SGSN)

Description

corresponding to that of said screen.

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  PROCESS FOR TETRA "Ee" TDEPROCEDuRE FOR THE USE OF [OLATIO "E ODE" DA "SYSTEM"

RA ["O (OMU" IC * T # ONS OBES

  The present invention deals with the world of the world of public transport. InvenDon is about more polcukAremen1 LocoUsofon SeIces can be used in these systems, to determine

  GIGOPROPIC POSI1ON OF THE WORLD OF 110 NAMES.

  For example, in the form of the Common Clobol for Common Funds, its LCS LoCofon Sees opeRs have been named in the 3 OPP TS 43.059 publication for 3CPP, 3'd

Cenro110n Ponershlp Proiec1).

  From a single source, in these systems, one selects the selections in the mode in the mode mode. In this case, you will be able to use the PRS mode [Cenel Pocke RoLlo Selce]. The drcub mode selections and the mode selections lead to different stoic orchids, and implAmentofons

  dLRentes for locololoNon selections.

  For example, for example, a model of a S / CPRS system for example is shown in Figure 1. It essentially compiles: - Bone or BTS CBOs Tronscelver S10hon and relocates to standard or SLE cells. VOBITe o1Ion), and control of BSE or BSC oil (for Bose oNon Contl ('in onglobD a set of S of BSC on 1 or oops of bose ofons, or BSS (for "Bose Stlon Substem"), - EnDs #es that nodes of suppo FRS seeun, or SGS (SeEng F Suppod Node), in lofon of a po ocle the BSS, ou1 pod o d in that nodes of ppod CP of 1nsh or GS Gotewoy GPRS Suppo Node (, themselves in rdotlon ovec of rseoux

SO higher (not 111ustrAs).

  G eneral management of BSS trainin g an O ns or N o rm a ness (for the Access Neoproducts of pe rs ng SGSN, 104341ND PR104341 Poc

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  GGSN, form (with other equipment) the heart of network, or CN (for Core Network.) According to the layered architecture used to describe these systems, one distinguishes, on the interface "Um" between MS and BSS , in order of increasing levels: - an RFGSM layer, - a MAC layer (<Medium Access Control>,

  - a layer RLC ("Radio Link Control").

  Likewise, on the "Gb" interface between BSS and SGSN, there is: - a layer L1 bis, - a layer "Network Service",

  a BSSGP layer ("BSS GPRS Protocol").

  Between MS and SGSN, an upper layer, or LLC layer ("Logical Link Control") allows exchange of frames called LLC frames, formed from higher level data units. In LLC frames these units of data

  are called LLC-Protocol Data Units (LLC-PDUs).

  The LLC-PDU data units are then segmented in the MAC / RLC layer to form blocks called RLC data blocks (RLC data blocks) .The RLC data blocks are then formatted to the required format.

  transmission on the interface "Um", in the physical layer.

  In addition, higher level signaling protocols are also provided, including for radio resource management or GRR ("GPRS Radio Resource Management"), mobility management or GMM ("GPRS Mobility").

  Management "), session management or SM (" Session Managemenh "), ... etc.

  In particular, according to the radio resource management protocol, different modes are possible for mobile payment, in packet mode: a mode called "packet transfer mode", in which resources are allocated temporarily, when data is actually to be transmitted during of a communication, these resources forming a temporary virtual channel or TBF ("temporary block flow") allowing a transfer of data between mobile station and résacu, for a given direction of transmission,

  a mode called "pacLet idle mode", in which no TBF is established.

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  By contrast, in circuit mode, the mode in which resources are allocated to a mobile station is called dedicated mode, these resources then being dedicated resources allocated to the mobile station for the duration of the communication. mobility management protocol, different procedures are provided according to which, during a GPRS session, in a state called "Ready" state, a mobile station MS informs the SGSN of any change of cell, by means of an update message. cell day, while in a state called << Standby >> state a mobile station MS informs the SGSN of any change of routing area (or RA, for "Routing Area"), by means of an update message a routing area corresponding to a set of cells.) Similarly, in a state called "Idie" state outside a GPRS session, a location update of the mobile station MS is performed if the mo station bile changes routing area. These proce- dures for the mobility management protocol thus make it possible to locate to a certain extent the mobile stations (ie in the measure necessary to the functioning of the system), but their accuracy is much lower than that provided by the localization services, since they make it possible to know, at best, only the cell in which

find the mobile station.

  For packet mode services, the location services are implemented in the following manner, recalled in connection with FIGS. 2 to 5, taken from the

  3GPP specification TS 43.0; 9 previously cited.

  Location service support entities are provided, in particular in the access network, with a Serving Mobile Location Center (SMLC) entity, on receipt of a request transmitted by an entity of the core network, the coordination of the various actions necessary for the provision of these location services such as: requiring radio measurements required for the location of the mobile station MS, transmitting the results of these measurements to an appropriate calculation function, receiving the result of this caleul function,

  retransmit this result in response to the request received.

  As recalled in FIG. 2, for a mobile station MS to be located (or mobile target station): 104341 / MA / NMND P: \ 10434 1 P.doc - in a step l, the server SGSN sends to the BSS server a request for localization of the mobile station MS, in a message "BSSGP Perform Location Request">, in a step 2, a location procedure is implemented, this procedure involving signaling exchanges between the entities BSS, SMLC and MS, - in a step 3, the BSS sends the SGSN its response to the localization request in a message, in a "BSSGP Perform Location" message.

Response ".

  Figure 3 recalls the location procedure step: - in a step 4, the BSS sends a request to the SMLC in a message "BSSAP-LE Perform Location Request", - in a step 5, the SMLC coordinates the different actions necessary, including sending the necessary signaling messages 1 5, - in a step 6, the SMLC sends its response to the BSS, in a message

  "BSSAP-LE Perform Location Response".

  Figure 4 recalls the protocol layers used to support the corresponding signaling between MS and SMLC. In this figure, in the order: AT in the mobile station MS: - a GSM RF layer, a MAC layer ("Medium Access Control", - a Radio Link Control (RLC) layer, - an LLC layer; ("Logical Link Control"), - a TOM layer ("Tunneling Of Messages"), - a Radio Resource LCS Protocol (RRLP) layer, À in the BSS, at the "Um" interface with the MS mobile station : - an RFGSM layer, - a MAC layer ("Medium Access Control", - an RLC layer ("Radio Link Control"), A in the BSS, at the "Gb" interface with the SGSN: - a layer Ll bis , 104341 / MA / NMND P: 104341 P.doc

2831,381

- a network service layer,

  a BSSGP layer ("BSS GPRS Protocol").

  In the SGSN, at the interface "Gb" with the BSS: - a layer Ll bis, a layer "Network Service", - a layer BSSGP ("BSS GPRS Protocol"), - a layer LLC ("Logical Link Control "),

  a TOM (Tunneling Of Messages) layer.

  in the BSS, at the "Gb" interface with the SGSN: - a layer L1 bis, - a layer "Network Service", - a layer BSSGP ("BSS GPRS Protocol"), A in the BSS, at the interface "Lb" with the SMLC: - a Message Transfer Part (MTP) layer, - a Signaling Connection Control Part (SCCP) layer, - a BSSAP-LE ("Base Station System Application part - LCS Extension") layer. - a BSSLAP ("Base Station System Application Part") layer, A in the SMLC, at the "Lb> 'interface with the BSS: an MTP (" Message Transfer Part ") layer, - an SCCP (" Signaling ") layer. Connection Control Part "), - a BSSAP-LE (" Base Station System Application Part - LCS Extension ") layer, - a BSSLAP (" Base Station System Application Part ") layer,

  an RRLP (Radio Resource LCS Protocol) layer.

  On the "Gb >> and" Um "interfaces, the corresponding signaling uses the signaling resources of the GSM / GPRS system.On the" Lb "interface between SMLC and BSS, the corresponding signaling uses specific resources, provided

  specifically for these location services.

  In addition, a procedure is provided for keeping a SMLC informed of cell changes of a mobile station during the execution of a locating procedure. Such a procedure is recalled in Figure 5: 104341 / MA / NMND P: \ 104341P.doc

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  in a step 7, the mobile station MS detects a cell change and, as the case may be, sends a cell update message or a Routing Area Update message ("Routing Area Update"). >>) at the SGSN, - in a step 8, the SGSN sends a message or unit of data <BSSGP FLUSH-LL "to the BSS; such a message is defined in the specification 3GPP TS 48.018; it allows a re-routing, in the downstream direction (ie network to mobile stations) of LLC PDU data units, from an old cell (before cell change) identified by a "BVCl (old)" information to a new cell (after cell change) identified by "BVCl (new)" information ("BVCI" being used for "BSSGP Virtual Connection Identifier") - in a step 9, the BSS sends an acknowledgment to the SGSN in the form of a message or data unit "BSSGP FLUSH-LL-ACK" (as also defined in the 3GPP specification TS 48.018), - in a step 10, the BSS sends the SMLC a message "BSSAP-LE Perform Location Information> >, this message containing the identification of

the new cell.

  However, it is understood that the execution of a localization procedure can not be continued in all cases, and that in certain cases such execution must be suspended by the server SGSN, in particular in the case where the cell change corresponds to a change of BSS (indeed, in this case, ie SMLC in

  load of the localization procedure may no longer be the same).

  However, the only knowledge of the identification of the new cell does not allow the server SGSN to determine whether the execution of a localization procedure should be suspended or not. To determine whether this execution should be suspended, it would be appropriate for the SGSN to have knowledge of the distribution of cells into different BSSs. However, the SGSN does not have, through the "Gb" interface, a vision of the BSS, because it manages only, via this interface, entities called NSE ("Network Service Entity"). In addition, the distribution of cells into different BSS

  does not coincide with the distribution of cells into different NSEs.

  In particular, such a distribution may be made according to operational criteria and to 104341 / MA / NMND P: \ 104341 P.doc

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  This may be different depending on whether one is looking at the access network (for the BSS) or from the point of view of the network core (for the NSE). There can thus be one or more NSEs by BSS. For the definition of NSE entities we can refer in particular to 3GPP specification TS 48.016, relating to the "Network Service" layer. A problem for the server SGSN is therefore to determine when the execution of a current loca lization procedure should be suspended, in the case

cell change.

  A solution to this problem has been proposed in the document 3GPP TSG GERAN WG2 # 6bis, Aix-en-Provence, France, October 22-26, G2-010232, Agenda item 7.2.5.9. This solution is simply to consider that if the cell change is an inter-NSE change, then the SGSN suspends the execution of (or

  English "abort") the current location procedure.

  As the applicant has observed, one of the drawbacks of such a solution is that according to the way in which the cells are distributed between different NSEs, this can lead to a situation where the execution of such a procedure can be suspended as a result of any cell change, while the original purpose was to suspend this execution as a result of a BSS change. For example, this may compromise any architecture based on distributed NSE entities, where one can have a relatively large number of NSEs per BSS (eg

  example because the NSE entities are relatively smaller).

  The present invention is intended in particular to avoid such disadvantages.

  One of the objects of the present invention is thus a method for the processing of procedure for packet location services in a mobile radio communication system, said procedure being initiated by means of a request transmitted to a subsystem of radio stations. server base by a server support node for packet mode services, and said method being substantially characterized in that the server support node for packet mode services suspends execution of said procedure if said procedure can not be maintained by the sub-server. -server base station system during a

cell change.

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  According to another feature, the server base station subsystem indicates to the server support node for packet mode services whether it can

  maintain said procedure during a cell change.

  According to another feature, the server base station subsystem indicates to the server support node for packet mode services whether it can maintain said host during a cell change, in a message of the server base station subsystem.

type "BSSGP FLUSH-LL-ACK".

  According to another characteristic, a message of the type "BSSGP FLUSH-LL-

  ACK "contains: - an indication that the current location procedure is

maintained or canceled.

  According to another characteristic, a message of the type "BSSGP FLUSH-LL-

  ACK "further contains the following information, if received in a message of type" BSSGP FLUSH-LL ": -" BVCI (new) ", or identification of new cell, after cell change, -" NSEI (new ) ", or identification of new NSE service entity,

after cell change.

  According to another feature: - the information "BVCl (new)" is included in a message of type "BSSGP FLUSH-LL-ACK" only if the current location procedure is maintained, - the information "NSEl (new) "is included in a message of type" BSSGP FLUSH-LL-ACK "only if the information" BVCl (new) "is included and if the information" NSEl (new) "has been received in a message of

type "BSSGP FLUSH-LL".

  According to another feature, in the case where said procedure can be maintained by the subsystem of server base stations during a cell change, the execution of said procedure is continued, using

  corresponding location context information.

  According to another characteristic, the base station subsystem occludes corresponding location context information, from the node of

  server support for packet mode services.

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  The present invention also relates to a mobile radio network equipment, and a mobile radio system, comprising means adapted to implement a method according to the invention.

present invention.

  Other objects and features of the present invention will be apparent to

  reading the following description of examples of reclisation, made in relation to the

  attached figures in which: - Figure 1 (described above) is intended to recall the general architecture of a cellular GSM / GPRS mobile radio system, - Figures 2, 3, 4 and 5 (previously described ) are intended to recall the implementation of an LCS ("LoCation Services") localization procedure, in a GSM / GPRS type system, in packet mode, - Figure 6 is intended to illustrate an example of a method according to the invention. By way of example, in the following, we consider the case of a LCS (LoCation Services) type localization procedure, in a GSM / GPRS type system, in packet mode. invention is not limited to one

example.

  According to one aspect of the invention, an example of a method according to

the invention is as follows.

  o If an inter-NSE cell change occurs for a target MS mobile station during a localization procedure: - in the case where the current LCS procedure can be maintained by the BSS during the cell changeover (especially during cell selection), that is, in the case of intra-BSS and inter-NSE cell change, the SGSN does not suspend the execution of the localization procedure, - in the case where the LCS procedure in course can not be maintained by the BSS during the cell change (especially during a re-selection of cells), ie in the case of cell change 104341 / MA / NMND P: \ 104341 P.doc 1 o 2831381 inter-BSS and inter-NSE, the SGSN suspends the execution of (or in English

  << abort >>) the location procedure.

  O If an intra-NSE cell change occurs during the procedure

  location, the SGSN does not suspend the execution of this procedure.

  In another aspect of the invention, the BSS indicates to the SGSN whether it can

  maintain a localization procedure in progress during a cell change.

  In particular, as indicated above, this allows the SGSN to determine whether

  suspend or not the execution of this current localization procedure.

  Advantageously, the BSS indicates to the SGSN whether it can maintain said procedure during a cell change, in a message of the type "BSSGP

FLUSH-LL-ACK ".

  For example, in the example illustrated in FIG. 6, steps 7 ', 8', 10 'may be similar to steps 7, 8, 10 of FIG. 5, and in step 9', the message << BSSGP FLUSH-LL-ACK "transmitted by the BSS to the SGSN may be used to provide an indication that the BSS may or may not maintain the

  localization during cell change.

  The message "BSSGP FLUSH-LL-ACK" then contains: - an indication that the current location procedure is

  maintained (or "maintained" in English) or canceled (or "cancellad" in English).

  In the case where the localization procedure is maintained, the following information may also be included in this message (if present in the message "BSSGP-FLUSH-LL" received in step 8 '): - "BVCI ( new) "(or identification of the new cell, after cell change (" BVCI "being used for" BSSGP Virtual Connoction Identifier "), -" NSEI (new) ") (or identification of new NSE service entity, after change cell ("NSEI" being used for "Network

Entit Service, v Identify ").

  For more details on the information "BVCI", "NSEI", "BVCl (new)",

  "NSEl (new)", we can reiterate in particular the specification 3GPP TS 48.018.

  Advantageously: 104341 / MA / NMND P: 104341 P.doc

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  - the BVCl (new) lnrmo1on to the BSSOP FLUSH-LL-ACK messge only the current locobsofon setting is less, - FFnformofon NSEnew) is included in the FLUSH-LL ACK message only Finformo110n B = # n) es1 Inclusive and Unrmotion to NSEnew) e gues messge BSSCP FLUSH LL n. Following a wave of lnnDon, we have no difficulty in using the SSN or BSS fl ow of a BSSCP FLUSH-LL eduA message according to F6pe 8S, not only for the sake of unites of LLC-PDU data going downstream. the follow up of a ch o ngement of cel te u (com me celo es1 oduel ly the cos of ops lo sp6c + kofon 30PP TS 48.018), month Agilement to re-rour con1-e locolLotion (cesh6-dire a set of relational Enformoilons one ofon mobe for a pcdu of coosofon in neck), one of perm lo

  procedure of locoGsoNon of being able to be lifted, oprAs this lengthening of cenule.

  Given this example, this re-rouioge is EnIerne or BSS: You cono-e of locoUschon does not put in the SGSN of a enh NSE Fri a ou1, month c'e

  BSS, which spreads out the same size as this cone.

  Get one example, from a centroSlice or high-level SGSN management, if these connews for SSN, o = SSN for a storytag I locate in a message of BSSCP FLUSH-LL or quivolenI . Lo pren invenhon o AgoTemen1 for obb1 a equipi1 of seou de rodiocommunicofons mobJes bel that name nud of suppo seur for sef in mode poqu {SN), soume of nozzle hon {BSSD, a sIAme of rodiocommunicofons mobe compoNonI odop16 means for

  HOW TO PROCEED WITH A PROCESS WILL FOLLOW TO PRESENGE ENVENHON.

  podicubar of the first means does not require a lot of money for the man of the means, the means do not require 61 darters

  The size of the grain is greater than that which has previously been 616 per cent.

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  ReV [NDICIO "S 1. ProcAdA for the procedure procedure for pouch-based locolbtion procedures for a mobile communiCon-mobile system, the 1st or 6th procedure for a homonymous request to a subset of bose seismic instructions (BSS) by a node of the processor in the QCSN mode), the procedure of the procedure is such that the node of the packet mode subsystem suspends the execution of the lodite procedure. The node of the procedure can not be maintained by the subsystem of s1hons

  of his sister hang a chongemen1 of ceu.

  2. PcAdA according to claim 1, corod6dsA in that the sub-sys1Ame of sSeSnS sSeSSeS (BSS) Indicates or node of suppo seeur for seSces in mode poque1 {SSH) sl may1 mOntrAnt of procDure pendon1 a chongemen

of cell.

  3. Procede according to lo rendicofon 2, cohsA in that the subset of bose (BSS) orbits of (bss) Endique or nud of suppodeur for poSe mode (SGSN) sl can mointenk of procAdure pendon1 a chongement of this #le , issued by Messrs. BSSCP FLUSH-LL-ACK 4. Procedure in accordance with Rule 3, CoroctArbd in that the message of BSSP FLUSH-LL-ACK to be sent to - in accordance with the terms of the locoUsofon procedure

monue or onnul.

  S. Procada, according to paragraph 4, corre- sponding in that the message of BSSCP FLUSH-LL-ACK is in accordance with the instructions given in a message of BPSOP FLUSH-LL-BVCI (new), or FdenfcoNo new shell, oprs cell choke, -, SEI {new), or new sefce SEE identification,

op ong_ of.

  6. A method according to claim 5, wherein the BVCI instrument is enclosed in a BSSCP FLUSH-LL-ACK messenger only when the locomotion is in progress, 104341D P1S41Edoc

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  - The information <NSEl (new) "is included in a message of type" BSSGP FLUSH-LL-ACK "only if the information" BVCl (new) "is included and if the information" NSEl (new) "was received in a message like

"BSSGP FLUSH-LL".

  Method according to one of Claims 1 to 6, characterized in that in

  the case where said procedure can be maintained by the subsystem server base stations (BSS) during a cell change, the execution of said procedure is continued, using corresponding context information

location.

  8. Method according to claim 7, characterized in that the base station subsystem (BSS) acquires corresponding context information from

  localization of the server support node for packet mode services (SGSN).

  9. Mobile radio resacu equipment, incorporating

  means for implementing a method according to one of claims 1

  to 8. 10. Mobile radio system, including means

  adapted to implement a method according to one of claims 1 to 8.