(19)
(11)EP 2 606 680 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
22.07.2020 Bulletin 2020/30

(21)Application number: 12823733.6

(22)Date of filing:  16.08.2012
(51)International Patent Classification (IPC): 
H04W 48/10(2009.01)
(86)International application number:
PCT/CN2012/080211
(87)International publication number:
WO 2013/023608 (21.02.2013 Gazette  2013/08)

(54)

ENHANCED ACCESS CONTROL IN LTE ADVANCED SYSTEMS

ERWEITERTE ZUGANGSKONTROLLE IN ERWEITERTEN LTE-SYSTEMEN

CONTRÔLE D'ACCÈS AMÉLIORÉ DANS DES SYSTÈMES LTE AVANCÉS


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 16.08.2011 US 201161524118 P
14.08.2012 US 201213585810

(43)Date of publication of application:
26.06.2013 Bulletin 2013/26

(73)Proprietor: HFI Innovation Inc.
Zhubei City, Hsinchu County 302 (TW)

(72)Inventor:
  • HSU, Chia-Chun
    Taipei City Taiwan 106 (TW)

(74)Representative: Habermann, Hruschka & Schnabel 
Patentanwälte Montgelasstraße 2
81679 München
81679 München (DE)


(56)References cited: : 
EP-A1- 3 062 562
WO-A1-2011/087041
CN-A- 102 045 810
WO-A1-2009/096833
CN-A- 101 969 635
  
  • TELEFON AB LM ERICSSON ET AL: "Realizing Extended Access Barring", 3GPP DRAFT; GP-110355, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. TSG GERAN, no. Chengdu; 20110304, 3 March 2011 (2011-03-03), XP050486659, [retrieved on 2011-03-03]
  • '3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Service accessibility (Release 11)' 3GPP TS 22.011 V11.0.0 30 June 2011, XP050553344
  • LG ELECTRONICS INC.: 'Further Discussion on EAB' 3GPP TSG-RAN WG2 #74, R2-113339 13 May 2011, XP050495447
  • ZTE: "Discussion on fast method for dynamic access control", 3GPP DRAFT; R2-112865 DISCUSSION ON FAST METHOD FOR DYNAMIC ACCESS CONTROL, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG2, no. Barcelona, Spain; 20110509, 3 May 2011 (2011-05-03), XP050495267, [retrieved on 2011-05-03]
  • INTEL CORPORATION: "EAB support", 3GPP DRAFT; R3-120165-EAB-DISCUSSION, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG3, no. Dresden, Germany; 20120206 - 20120210, 30 January 2012 (2012-01-30), XP050566515, [retrieved on 2012-01-30]
  • "LTE; Evolved Universal Terrestrial Radio Access Network (E-UTRAN); S1 Application Protocol (S1AP) (3GPP TS 36.413 version 10.3.0 Release 10)", TECHNICAL SPECIFICATION, EUROPEAN TELECOMMUNICATIONS STANDARDS INSTITUTE (ETSI), 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS ; FRANCE, vol. 3GPP RAN 3, no. V10.3.0, 1 October 2011 (2011-10-01), XP014068386,
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

FIELD OF INVENTION



[0001] The disclosed embodiments relate generally to Machine type communications, and, more particularly, to enhanced access control for machine type communications in LTE-Advanced systems.

BACKGROUND OF THE INVENTION



[0002] Machine type communication is a form of data communication that involves one or more entities that do not necessarily need human interaction. A service optimized for machine type communication differs from a service optimized for human-to-human (H2H) communication. Typically, machine type communication services are different to current mobile network communication services as it involves different market scenarios, pure data communication, lower cost and effort, and a potentially very large number of communicating terminals with little traffic per terminal.

[0003] The terms Machine-to-Machine (M2M) and Machine-Type Communications (MTC) are used to describe use cases and illustrate the diverse characteristics of machine type communication service. M2M and MTC devices will be part of the next generation wireless networks to enable "internet of things". Potential M2M and MTC applications include security, tracking and tracing, payment, health, remote maintenance/control, metering, and consumer devices. The main characteristics of machine type communication services include low mobility, time controlled, delay tolerant, packet-switched only, small data transmissions, mobile originated only, infrequent mobile terminated, MTC monitoring, priority alarm, secure connection, location specific trigger, network provided destination for uplink data, infrequency transmission, and group based MTC features.

[0004] The end-to-end application between an MTC device and an MTC server or between two MTC devices is provided by 3GPP LTE systems. A 3GPP LTE system provides transport and communication services optimized for MTC. MTC traffic, however, may not be controlled by the network/core network. For example, an MTC application may request many MTC devices to do "something" at the same time, resulting in a large number of M2M devices trying to access the wireless service during a very short amount of time. As a result, many MTC devices may send a large number of random access channel (RACH) preambles and thereby causing high RACH collision probability. In addition, when a core network entity goes down, there is no mechanism to postpone the MTC devices from continuous access attempts. Consequently, many MTC devices are roamers and may all move to local competing networks when their own serving network fails, which may potentially cause traffic overload in the not (yet) failed network(s).

[0005] Figure 1 (Prior Art) illustrates a radio network congestion use case in an LTE network 100. LTE network 100 comprises a MTC server 110, a packet data network gateway (PDN GW) 120, a serving GW 130, two base stations eNB141 and eNB142, and a plurality of M2M devices. Radio network congestion occurs when massive concurrent data transmission takes place in some MTC applications, as illustrated in Figure 1. One of the typical applications is bridge monitoring with a mass of sensors. When a train passes through the bridge, all the MTC sensors transmit monitoring data almost simultaneously. The same thing happens in hydrology monitoring during the time of heavy rain, and in building monitoring when intruders break in. Therefore, it is desirable that the network is optimized to enable a mass of MTC devices in a particular area to transmit data almost simultaneously.

[0006] Figure 2 (Prior Art) illustrates a core network congestion use case in an LTE network 200. LTE network 200 comprises a MTC server 210, a packet data network gateway (PDN GW) 220, a serving GW 230, two base stations eNB241 and eNB242, and a plurality of M2M devices. For many MTC applications, a large number of MTC devices are affiliated with a single MTC user (e.g., MTC user 250). These MTC devices together are part of a MTC group (e.g., MTC group 260). For example, MTC user 250 is associated with MTC group 260, and MTC user 250 owns MTC server 210. The MTC devices in MTC group 260 communicate with MTC server 210. Typically, the MTC devices in the same MTC group are scattered over the network in such a way that the data simultaneously sent by the MTC devices in any particular cell is limited and will not cause a radio network overload. However, when a high number of MTC devices are sending/receiving data simultaneously, data congestion may occur in the mobile core network or on the link between the mobile core network and the MTC server where the data traffic related to the MTC group is aggregated, as illustrated in Figure 2. Therefore, it is desirable that a network operator and the MTC user have means to enforce a maximum rate for the data sent/received by the same MTC group.

[0007] Access Class Barring (ACB) is a mechanism to limit the number of simultaneous access attempts from certain MTC devices. All UEs (e.g., MTC devices) are member of one out of ten randomly allocated mobile populations, defined as access class 0 to 9. The population number is stored in UE's SIM/USIM. In addition, the UEs may be members of one or more out of five special categories (e.g., Access Class 11 to 15), also stored in the SIM/USIM. Under the ACB mechanism, the network operator may prevent certain UEs from making access attempts or responding to pages in specific areas of a PLMN based on the corresponding access class. In addition to the ACB mechanism, other enhanced access control solutions are sought for optimized MTC services.

[0008] Publication Telefon AB LM Ericsson et al. "Realizing Extended Access Barring", 3GPP DRAFT; GP-110355; vol. TSG Geran, no. Chengdu, 20110304, 3 March 2011, generally pertains to an access control method in a 3GPP LTE-Advanced network.

[0009] LG ELECTRONICS INC.: "Further Discussion on EAB",3GPP TSG-RAN WG2 #74, R2-113339, refers to TS22.011 v10.3.0 and further discloses that a broadcast SIB comprises EAB information and that a UE configured for EAB shall use its allocated ACs when evaluating the EAB information, in order to determine if its access to the network is barred.

SUMMARY OF THE INVENTION



[0010] The present invention refers to methods for enhanced access control for machine-type communications (MTC) in a 3GPP LTE-Advanced network according to claim 1. An MTC device is configured for enhanced access barring (EAB). When the MTC device attempts access to the network, the NAS layer checks whether EAB is applicable for the MTC device. If yes, then the NAS layer forwards EAB configuration to the AS layer for further EAB control. Based on the EAB configuration, a base station broadcasts EAB information to UEs via system information block. The EAB information indicates whether barring is applied to a number of EAB categories and a number of access classes. Based on the EAB information, the MTC devices performs EAB for access attempt to RRC. If access is not barred under EAB, then the MTC device further performs ACB for access attempt to RRC. By combining EAB mechanism with ACB mechanism, additional flexibility of access control is achieved.

BRIEF DESCRIPTION OF THE DRAWINGS



[0011] The accompanying drawings, where like numerals indicate like components, illustrate embodiments of the invention.

Figure 1 (Prior Art) illustrates a radio network congestion use case in a 3GPP LTE network.

Figure 2 (Prior Art) illustrates a core network congestion use case in a 3GPP LTE network.

Figure 3 illustrates a 3GPP LTE network that supports Machine-Type Communication (MTC) in accordance with one novel aspect.

Figure 4 illustrates an enhanced access barring (EAB) mechanism in accordance with one novel aspect.

Figure 5 illustrates one example of EAB information broadcasted via a system information block (SIB).

Figure 6 illustrates a method of providing enhanced access barring in accordance with one novel aspect.

Figure 7 is a flow chart of a method of enhanced access barring for optimized machine-type communication in accordance with one novel aspect.


DETAILED DESCRIPTION



[0012] Reference will now be made in detail to some embodiments of the invention, examples of which are illustrated in the accompanying drawings.

[0013] Figure 3 illustrates a 3GPP LTE network 300 that supports Machine-Type Communications (MTC) in accordance with one novel aspect. 3GPP LTE network 300 comprises an MTC server 311 that provides various MTC services to an MTC user 312 by communicating with a plurality of MTC devices (e.g., MTC device 314 as illustrated in Figure 3). In the example of Figure 3, MTC server 311, MTC user 312, and a packet data network gateway (PDN GW) 313 belong to part of a core network 310. MTC device 314 and its serving base station (eNB) 315 belong to part of a radio access network (RAN) 320. MTC server 311 communicates with MTC device 314 through PDN GW 313, serving GW 316, and eNB 315. In addition, a mobility management entity (MME) 317 communicates with eNB 315, serving GW 316 and PDN GW 313 for mobility management of wireless access devices in 3GPP network 300. It is noted that, MTC device 314 is a type of user equipment (UE), and the term MTC is referred to as machine-to-machine (M2M) communication as compared to human-to-human (H2H) communication, while an MTC device is also referred to as an M2M device as compared to H2H device.

[0014] In the example of Figure 3, MTC server 311 provides various MTC services/applications to MTC user 312 in application (APP) protocol layer through an established application-programming interface (API) 340. Typical MTC applications include security (e.g., surveillance system), tracking and tracing (e.g., pay as you drive), payment (e.g., vending and gaming machines), health (e.g., health persuasion system), remote maintenance/control, metering (e.g., smart grid), and consumer devices (e.g., eBooks). To provide the end-to-end MTC services, MTC server 311 communicates with the plurality of MTC devices in the 3GPP network. Each MTC device (e.g. MTC device 314) comprises various protocol layer modules to support the end-to-end MTC applications and data connections. In the application level, APP module 331 communicates with MTC server 311 in APP protocol layer (e.g., depicted by dashed line 341), which provides the end-to-end control/data. In the network or NAS level, NAS module 332 communicates with MME 317 in non-access stratum protocol layer (e.g., depicted by dashed line 342), which supports mobility management and other signaling functionality. In the radio network access (RAN) or AS level, RRC module 333 communicates with eNB 315 in radio resource control (RRC) protocol layer (e.g., depicted by dashed line 343), which takes care of broadcast of system information, RRC connection control, paging, radio configuration control, QoS control, etc.

[0015] Because the MTC server is not necessarily located inside the network operator domain, and because end-to-end MTC services may not necessarily involve the MTC server, MTC traffic is most likely not controlled by the network/core network. As a result, if a large number of MTC devices (e.g., much larger than the designed dimension, in terms of the number of UEs of a cell, or an eNB, or an MME) want to access wireless service during a short amount of time, a large number of random access channel (RACH) preambles sent from the MTC devices to their serving base station would likely to cause high RACH collision probability. Allocating extra RACH resource (slot or preambles), although may reduce collision probability, may lead to inefficient radio resource usage. Furthermore, when a core network went down, many MTC devices are roamers and all move to local competing networks when their own serving network fails, which would potentially overload the not (yet) failed network(s).

[0016] In one novel aspect, an enhanced access barring (EAB) mechanism is provided for the network operator to control access attempts from UEs that are configured for EAB in order to prevent overload of the access network and/or the core network. In congestion situations, the network operator can restrict access from UEs configured for EAB while permitting access from other UEs. Typically, UEs configured for EAB are considered more tolerant to access restrictions than other UEs. When the network operator determines that it is appropriated to apply EAB, the network broadcasts EAB information to provide EAB control for UEs in a specific area.

[0017] For example, upon an access attempt by MTC device 314, in NAS layer, MTC device 314 first checks whether EAB is configured and applicable for MTC device 314. If EAB is not configured or EAB is not applicable, then no further EAB control in AS layer (e.g., in RAN 320) is needed. If the NAS layer decided that EAB is configured and applicable for MTC 314, then further EAB check is needed in AS layer of MTC device 314. The AS layer EAB check is based on EAB information broadcasted from eNB 315. In AS layer, eNB 315 determines the EAB information based on EAB configuration transmitted from MME 315. The EAB information is then broadcasted to MTC device 314 via system information block. Upon acquiring the EAB information, MTC device 314 attempts RRC access subject to EAB control. Note that, if the network does not broadcasting the EAB information to UE, UE is still subject to access class barring (ACB) if ACB information is broadcasted. In addition, after the EAB check, if a UE is not barred based on the EAB information, then the UE is still subject to ACB if ACB information is broadcasted.

[0018] Figure 4 illustrates one embodiment of EAB mechanism in 3GPP LTE network 400. 3GPP LTE network 400 comprises a user equipment UE 401, a base station eNB 402, a mobility management entity MME 403, and a device management server 404. To facilitate the EAB mechanism, each UE device is configured for whether the device is subject to EAB control in its home public land mobile network (HPLMN). The device EAB configuration is based on device type (e.g., low priority MTC devices, devices are more tolerant to access restriction than normal UEs), based on UE behavior (e.g., bad behavior such as keep accessing a downed server), based on UEs having certain APN (e.g., certain applications are more tolerant to access restriction than other applications), or based on UEs in specific area (e.g., UEs in congested area). The device EAB configuration is signaled through an OTA protocol such as Open Mobile Alliance (OMA) Device Management (DM) protocol. In the example of Figure 4, device management server 404 sends the device EAB configuration 411 to UE 401. For example, if UE 401 is an MTC device, then it is configured subject to EAB control. Once the device EAB configuration is received by UE 401, it could be permanent and only be modified or removed by explicit signaling. In this invention, it is denoted that a MTC device shall apply EAB when it is configured by device management sever 404, the device EAB configuration can be a bit to force the MTC device to apply EAB in NAS/AS layer.

[0019] When the network operator determines that it is appropriated to apply EAB due to the congestion, MME 403 will send network EAB configuration 421 to the AS layer (e.g., eNB 402) for EAB control. The additional network EAB configuration mainly includes the following information: 1) what percentage of traffic from MTC traffic (e.g., 10%, 20%, 30%, ..., 100%) need to be barred, which is matched to how many access classes (AC) to be barred, 2) EAB categories to be barred, and 3) specific area for applying EAB. First, all UEs are members of one out of ten randomly allocated mobile populations, defined as access classes 0 to 9. The population number is stored in UE's SIM/USIM. In addition, UEs may be members of one or more out of five special categories (e.g., Access Classes 11 to 15), also stored in the SIM/USIM. The percentage of traffic needs to be barred is then mapped to how many access classes to be barred. For example, if 50% of MTC traffic needs to be barred, then UEs having access class 0-4 may be barred accordingly.

[0020] Second, each UE belongs to one of three specific EAB categories (a), (b), and (c) with respect to its roaming status. EAB category (a) is defined for normal UEs that are configured for EAB; EAB category (b) is defined for UEs that are configured for EAB, and are neither in their HPLMN nor in a PLMN that is equivalent to HPLMN (e.g., roaming UE); and EAB category (c) is defined for UEs that are configured for EAB, and are neither in the PLMN listed as most preferred PLMN of the country where the UE is roaming in the operator-defined PLMN selector list on the SIM/USIM, nor in their HPLMN nor in a PLMN that is equivalent to HPLMN. When EAB mechanism is applied, one or more EAB categories may be barred.

[0021] Third, MME 403 may determine a specific area that EAB mechanism is applied. For example, if radio network congestion occurs in an area with regard to a number of concerned eNBs, then MME 403 sends the network EAB configuration only to those concerned eNBs. Other eNBs outside of the radio network congestion will not receive the network EAB configuration and thus will not perform any further EAB control. This way, EAB control is only applied in a limited number of relevant cells for more efficient access control.

[0022] Upon receiving the network EAB configuration 421, eNB 402 broadcasts EAB information 431 to UE 401, e.g., through system information block (SIB). The broadcasted EAB information 431 defines whether EAB applies to UEs having one of the three EAB categories. EAB information also includes extended barring information for access classes 0-9. Based on the EAB information, the AS network checks the UE EAB category and access class to determine whether access is barred. In the case of multiple core networks sharing the same access network (RAN sharing), the access network shall be able to apply EAB for the core networks individually. The concerned PLMN is included with EAB configuration.

[0023] Figure 5 illustrates one example of EAB information broadcasted via a system information block (SIB). Table 500 illustrates one example of system information block type 14 (e.g., SIB14). In SIB14, the EAB configuration parameters include common configuration and per-PLMN configuration. For each PLMN, the EAB configuration parameters include 1) enumerated EAB category 501, indicating which EAB categories to be barred, and 2) bitmap of barring access classes 502, indicating which access classes to be barred. The EAB information may also includes PLMN ID and associated barring parameters including barring factor and barring time. Because the EAB information is broadcasted to the UEs, each UE only needs to acquire EAB information in RRC_IDLE mode. In addition, only UEs that are configured for EAB will read the EAB information from SIB14. Normal UEs not configured for EAB do not need to acquire SIB14.

[0024] Figure 6 illustrates a method of providing enhanced access barring in mobile network 600 in accordance with one novel aspect. Mobile network 600 comprises an MTC device 610, an eNB 620, an MME 630, and a device management server 640. Initially, in step 651, MTC device 610 is configured for EAB by device management server 640. Later on, the network operator determines to apply EAB mechanism upon network congestion when MTC device 610 attempts to access the mobile network. In step 652, MME 630 checks EAB applicability of concerned eNB and sends network EAB configuration to eNB 620 if EAB is applicable. The EAB applicability for each MTC device depends on several factors. First, the MTC device has been configured for EAB (e.g., in step 651). Second, the attempted access is not an emergency call, or the MTC device does not belong to one of the special access classes (11-15). Third, the attempt access is delay tolerant (e.g., based on establishment cause of the access attempt).

[0025] In step 653, upon receiving the EAB configuration from MME 630, eNB 620 determines EAB information for the current cell and broadcasts the EAB information to MTC device 610 via SIB. To save power, MTC device 610 does not need to read the EAB information periodically. Instead, MTC device 610 receives an indication from eNB 620, e.g., the indication is a pre-defined tag on paging channel, and MTC device 610 in response reads the EAB information in the SIB. In addition, when EAB information changes, the value tag in SIB1 does not need to be changed. This way, normal UEs not subject to EAB do not need to re-acquire the SIB due to EAB information change.

[0026] Upon acquiring the EAB information, in step 654, MTC device 610 performs EAB access barring based on its EAB category and access class. If access is barred, MTC device 610 stops attempting to access the radio network. If access is not barred, MTC device 610 performs ACB (if MTC device 610 is configured for ACB and ACB information is broadcasted by eNB 620) in step 655. MTC device 610 can only attempt to access the radio network (e.g., start RACH procedure) after successfully passing both EAB and ACB. In step 656, MTC device 610 sends a RRC connection request to eNB 620. Additional flexibility of access control to the radio network can be achieved by applying both EAB and ACB for the same UEs.

[0027] If MTC device 610 is barred from accessing the radio network, then MTC device 610 may have more opportunities to access the radio network later, either via timer mechanism, or via changed EAB configuration. There are different ways to implementing access barring. In one embodiment, access barring is achieved via barring parameters including access probability (e.g., barring factor) and retry timer (e.g., barring time) performed at the UE side. In another embodiment, access barring is achieved via changed EAB information determined at the eNB side. For example, if 50% of MTC traffic is barred, then eNB 620 determines that access classes 0-4 are barred initially. Later on, eNB 620 determines that access classes 5-9 are barred such that each access class has similar access distribution. The updated EAB information is indicated to UE 610 by a pre-defined tag on paging channel.

[0028] Figure 7 is a flow chart of a method of enhanced access barring for optimized machine-type communication in accordance with one novel aspect. In step 701, a user equipment (UE) attempts to access a mobile network. Based on the type of device and the type of access, the NAS layer checks whether EAB is applicable for the UE. In step 702, the NAS layer checks whether the UE is configured with EAB (e.g., an MTC device type is configured with EAB). If no, then the UE performs access attempt to establish an RRC connection (step 705). If yes, then the NAS layer further checks if the access is for low priority access (e.g., Establishment Cause = delay tolerant access), or the access is a Mobile Originated (MO) session (e.g., Establishment cause = MO-signaling or MO data) (step 703). This is because MO session is typically delay-tolerant, as compared to Mobile Terminated (MT) session. If the answer is yes in step 703, then the UE performs access attempt to establish an RRC connection (step 705). If no, then the NAS layer further checks if the access is an emergency call, or the UE belongs to one of the special access classes 11-15 (step 704). The special access classes are allocated to specific high priority users as follows: class 15 for PLMN staff, class 14 for Emergency services, class 13 for Public Utilities, class 12 for Security Services, and class 11 for PLMN use. If the answer is yes in step 704, then the UE is not subject to EAB and performs access attempt to establish an RRC connection (step 705). If no, then the UE performs access attempt for RRC connection under the EAB mechanism (step 706).

[0029] Under the EAB mechanism, the AS layer further checks whether the UE is barred for access to RRC based on EAB information broadcasted from the serving base station. The EAB information contains the EAB category with respect to roaming and a list of access classes. In step 707, the UE checks whether its EAB category and access class is barred based on the EAB information. If the answer is yes, then access is barred for the UE for this access attempt. Otherwise, the UE checks whether access is barred under normal ACB mechanism (step 708).

[0030] Access Class Barring (ACB) is a mechanism to limit the number of simultaneous access attempts from certain UEs. As compared to H2H Access Class (AC), M2M Access Class (AC) may apply different access probability, barring parameters, and retry timer parameters. Such procedure may be implemented in application level, NAS level, or RAN level (e.g., RACH access level) access distribution. In application level access distribution, barring is done by prioritize access based on type of services. For example, different access probability is based on QoS requirement and/or delay-tolerant level of different applications. In NAS level access distribution, barring is done by access restriction, e.g., prioritize access based on service type, MTC server, and device ID (e.g. new MTC ID, international mobile equipment identity (IMEI), international mobile subscriber identity (IMSI), etc.). In RAN level access distribution, barring is done by applying different ac-BarringFactor in Access Class Barring mechanism. For example, different barring factors and retry timers are applied for MTC devices. By combining EAB mechanism with ACB mechanism, additional flexibility of access control is achieved.


Claims

1. A method, comprising:

receiving (652) an enhanced access barring, EAB, configuration from a mobility management entity, MME (630) by a base station (620) in a 3GPP LTE-Advanced mobile communication network, wherein the EAB configuration indicates a percentage of Machine-Type Communications, MTC, traffic to be barred and an EAB category to be barred;

determining EAB information by the base station (620) for a plurality of MTC devices (610), based on the EAB configuration, wherein the EAB information indicates which EAB categories to be barred (501) and which access classes of a number of access classes to be barred (502), referred to as first access classes, and wherein the percentage of MTC traffic to be barred is matched by the base station (620) to the number of access classes to be barred (502);

broadcasting the EAB information by the base station (620) to the plurality of MTC devices (610) via a system information block, SIB (500); and

transmitting by the base station (620) an indication that the EAB information is being broadcasted to the plurality of MTC devices (610), indicating that the updated EAB information in the SIB (500) can be read upon receiving the indication;

the method further comprising:

determining updated EAB information by the base station (620) for a plurality of MTC devices (610), wherein the updated EAB information indicates which EAB categories to be barred (501) and which second access classes of the same number but different from the first access classes to be barred (502);

broadcasting the updated EAB information by the base station (620) to the plurality of MTC devices (610) via a system information block, SIB (500); and

transmitting by the base station (620) a further indication that updated EAB information is being broadcasted to the plurality of MTC devices (610), indicating that the updated EAB information in the SIB (500) can be read upon receiving the indication.


 
2. The method of Claim 1, wherein the EAB category is associated with a roaming status of a MTC device (610) in a public land mobile network, PLMN.
 
3. The method of Claim 1, wherein each access class of the access classes to be barred is associated with a corresponding group of MTC devices.
 
4. The method of Claim 3, wherein a MTC device (610) stores one number out of ten randomly assigned to the MTC device (610), the stored number referred to as population number, in a Subscriber Identity Module or Universal Subscriber Identity Module, SIM/USIM, and wherein the population number is mapped to a corresponding access class.
 
5. The method of Claim 1, wherein the indication transmitted by the base station (620) is a predefined tag on a paging channel.
 


Ansprüche

1. Verfahren aufweisend:

Empfangen (652) einer Konfiguration einer verbesserten Zugriffssperre, EAB, von einer Mobilitätsverwaltungseinheit, MME (630), durch eine Basisstation (620) in einem 3GPP LTE-Advanced-Mobilkommunikationsnetz, wobei die EAB-Konfiguration einen Prozentsatz des zu sperrenden Machine-Type-Communications-, MTC, Verkehrs und eine zu sperrende EAB-Kategorie angibt;

Bestimmen einer EAB-Information durch die Basisstation (620) für eine Vielzahl von MTC-Vorrichtungen (610) auf der Grundlage der EAB-Konfiguration, wobei die EAB-Information angibt, welche EAB-Kategorien zu sperren sind (501) und welche Zugangsklassen einer Anzahl von Zugangsklassen zu sperren sind (502), die als erste Zugangsklassen bezeichnet werden, und wobei der Prozentsatz des zu sperrenden MTC-Verkehrs durch die Basisstation (620) an die Anzahl der zu sperrenden Zugangsklassen (502) angepasst wird;

Rundsenden der EAB-Information durch die Basisstation (620) zu der Vielzahl von MTC-Vorrichtungen (610) über einen Systeminformationsblock, SIB (500); und

Übertragen einer Anzeige durch die Basisstation (620), dass die EAB-Information zu der Vielzahl von MTC-Vorrichtungen (610) gesendet wird, was anzeigt, dass die aktualisierte EAB-Information in dem SIB (500) beim Empfang der Anzeige gelesen werden kann;

wobei das Verfahren ferner aufweist:

Bestimmen der aktualisierten EAB-Information durch die Basisstation (620) für eine Vielzahl von MTC-Vorrichtungen (610), wobei die aktualisierte EAB-Information anzeigt, welche EAB-Kategorien gesperrt werden sollen (501) und welche zweiten Zugriffsklassen mit der gleichen Anzahl, aber unterschiedlich von den ersten Zugriffsklassen gesperrt werden sollen (502);

Rundsenden der aktualisierten EAB-Information durch die Basisstation (620) zu der Vielzahl von MTC-Vorrichtungen (610) über einen Systeminformationsblock, SIB (500); und

Übertragen einer weiteren Anzeige durch die Basisstation (620), dass eine aktualisierte EAB-Information an die Vielzahl von MTC-Vorrichtungen (610) gesendet werden, was anzeigt, dass die aktualisierten EAB-Information in dem SIB (500) beim Empfang der Anzeige gelesen werden kann.


 
2. Verfahren nach Anspruch 1, bei dem die EAB-Kategorie einem Roaming-Status einer MTC-Vorrichtung (610) in einem öffentlichen Landmobilfunknetz, PLMN, zugeordnet ist.
 
3. Verfahren nach Anspruch 1, bei dem jede Zugangsklasse der zu sperrenden Zugangsklassen einer entsprechenden Gruppe von MTC-Vorrichtungen zugeordnet wird.
 
4. Verfahren nach Anspruch 3, bei dem eine MTC-Vorrichtung (610) eine von zehn Zahlen, die der MTC-Vorrichtung (610) zufällig zugewiesen wird, wobei die gespeicherte Zahl als Populationsnummer bezeichnet wird, in einem Teilnehmeridentitätsmodul oder Universal Subscriber Identity Module, SIM/USIM, speichert und bei dem die Populationsnummer auf eine entsprechende Zugriffsklasse abgebildet wird.
 
5. Verfahren nach Anspruch 1, bei dem die von der Basisstation (620) übertragene Anzeige ein vordefiniertes Tag auf einem Paging-Kanal ist.
 


Revendications

1. Méthode, comprenant les étapes consistant à :

recevoir (652) une configuration d'interdiction d'accès améliorée EAB, à partir d'une entité de gestion de mobilité, MME, (630) par l'intermédiaire d'une station de base (620) dans un réseau de communication mobile 3GPP LTE avancé, dans laquelle la configuration EAB indique un pourcentage de trafic de communications de type machine, MTC, à interdire et catégorie EAB à interdire ;

déterminer des informations EAB par l'intermédiaire de la station de base (620) pour une pluralité de dispositifs MTC (610), sur la base de la configuration EAB, dans laquelle les informations EAB indiquent les catégories EAB à interdire (501) et les classes d'accès d'un certain nombre de classes d'accès à interdire (502), appelées premières classes d'accès, et dans laquelle le pourcentage de trafic MTC à interdire est apparié par l'intermédiaire de la station de base (620) avec le nombre de classes d'accès à interdire (502) ;

diffuser les informations EAB par l'intermédiaire de la station de base (620) à la pluralité de dispositifs MTC (610) via un bloc d'informations système, SIB, (500) ; et

transmettre par l'intermédiaire de la station de base (620) une indication que les informations EAB sont diffusées à la pluralité de dispositifs MTC (610), indiquant que les informations EAB mises à jour dans le SIB (500) peuvent être lues lors de la réception de l'indication ;

la méthode comprenant en outre les étapes consistant à :

déterminer des informations EAB mises à jour par l'intermédiaire de la station de base (620) pour une pluralité de dispositifs MTC (610),
dans laquelle les informations EAB mises à jour indiquent les catégories EAB à interdire (501) et les secondes classes d'accès du même nombre mais différentes des premières classes d'accès à interdire (502) ;

diffuser les informations EAB mises à jour par l'intermédiaire de la station de base (620) à la pluralité de dispositifs MTC (610) via un bloc d'informations système, SIB, (500) ; et

transmettre par l'intermédiaire de la station de base (620) une indication supplémentaires que des informations EAB sont diffusées à la pluralité de dispositifs MTC (610), indiquant que les informations EAB mises à jour dans le SIB (500) peuvent être lues lors de la réception de l'indication.


 
2. Méthode selon la revendication 1, dans laquelle la catégorie EAB est associée à un état d'itinérance d'un dispositif MTC (610) dans un réseau mobile terrestre public, PLMN.
 
3. Méthode selon la revendication 1, dans laquelle chaque classe d'accès des classes d'accès à interdire est associée à un groupe correspondant de dispositifs MTC.
 
4. Méthode selon la revendication 3, dans laquelle un dispositif MTC (610) stocke un numéro sur dix attribué au hasard au dispositif MTC (610), le numéro stocké appelé numéro de population, dans un module d'identité d'abonné ou un module d'identité d'abonné universel, SIM/USIM, et dans laquelle le numéro de population est mappé par rapport à une classe d'accès correspondante.
 
5. Méthode selon la revendication 1, dans laquelle l'indication transmise par la station de base (620) est une étiquette prédéfinie sur un canal de radiomessagerie.
 




Drawing

















Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Non-patent literature cited in the description