Enhanced access control in LTE advanced systems
An enhanced access control method is proposed for machine-type communications (MTC) in a 3GPP LTE-Advanced network. 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.
1. A method comprising:
detecting a device enhanced access barring (EAB) configuration by a Machine-Type Communications (MTC) device in a mobile communication network, wherein the device EAB configuration indicates whether the MTC is configured with EAB such that the MTC is subject to restriction of any EAB category;
acquiring enhanced access barring (EAB) information from a base station by the MTC if the MTC is configured with EAB, wherein the EAB information indicates whether barring is applied to a number of EAB categories and a number of access classes broadcasted via a system information block;
performing enhanced access barring by the MTC device for radio resource control (RRC) connection based on the EAB information; and
performing access class barring (ACB) for RRC connection if the MTC device is configured for ACB and is not barred by the enhanced access barring.
2. The method of claim 1 , wherein an EAB category is associated with a roaming status of the MTC device in a public land mobile network (PLMN).
3. The method of claim 1 , wherein the MTC device stores a 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.
4. A method comprising:
detecting a device enhanced access barring (EAB) configuration by a Machine-Type Communications (MTC) device in a mobile communication network, wherein the device EAB configuration indicates whether the MTC is subject to EAB;
acquiring enhanced access barring (EAB) information from a base station by the MTC if the MTC is subject to EAB, wherein the EAB information indicates whether barring is applied to a number of EAB categories and a number of access classes broadcasted via a system information block (SIB), and wherein the MTC device checks schedule information in SIB 1 to decide if the EAB information in SIB 14 is available;
performing enhanced access barring by the MTC device for radio resource control (RRC) connection based on the EAB information; and
performing access class barring (ACB) for RRC connection if the MTC device is configured for ACB and is not barred by the enhanced access barring.
5. The method of claim 4 , wherein the MTC device reacquires SIB 1 and SIB 14 for updated EAB information, and wherein the MTC device performs enhanced access barring for RRC connection using the updated EAB information.
6. The method of claim 1 , wherein the MTC device is configured for EAB by an Open Mobile Alliance (OMA) Device Management (DM) server.
7. The method of claim 1 , wherein the EAB information further comprises a public land mobile network (PLMN) ID and associated barring parameters including a barring factor and a barring time.
8. The method of claim 1 , further comprising:
determining whether EAB is applicable to the MTC device, wherein the MTC device is applicable for EAB only if the MTC device is configured for EAB.
9. The method of claim 8 , wherein the MTC device is not applicable for EAB if the MTC device belongs to one of a special access classes 11-15 or if the access attempt belongs to an emergency call.
10. The method of claim 8 , wherein the MTC device is applicable for EAB if an establishment cause indicates a mobile originated (MO) signaling or MO data.
11. The method of claim 8 , wherein the MTC device is applicable for EAB if an establishment cause indicates a delay tolerant access.
12. A method, comprising:
receiving an enhanced access barring (EAB) configuration from a mobility management entity by a base station in a mobile communication network, wherein the EAB configuration indicates a percentage of traffic to be barred and an EAB category to be barred;
determining EAB information for a plurality of user equipments (UEs) based on the EAB configuration, wherein the EAB information includes the EAB category to be barred and one or more access classes to be barred based on the percentage of traffic to be barred;
broadcasting the EAB information to the plurality of UEs via a system information block; and
indicating the EAB information become available or removed via a pre-defined tag on a paging channel.
13. The method of claim 12 , wherein the EAB category is associated with a roaming status of a UE in a public land mobile network (PLMN).
14. The method of claim 12 , wherein the percentage of traffic is matched to the number of access classes, and wherein each access class is associated with a corresponding group of UEs.
15. The method of claim 14 , wherein a UE stores a 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.
16. The method of claim 12 , wherein the base station indicates updated EAB information via the same tag value on the paging channel.
17. The method of claim 16 , wherein the base station determines a first number of access classes in the EAB information, and wherein the base station determines a second number of access classes in the updated EAB information.