1. A method of using a Third Generation Partnership Project (3GPP) Evolved Packet Core (EPC) based wireless Access Network (AN) to enable attachment of a Machine-to-Machine (M2M) entity to an M2M Service Provider (SP) network chosen by the M2M entity, wherein the method comprises performing the following steps using the AN:
receiving an initial request from the M2M entity to attach to the M2M SP network, wherein the initial request contains an entity-specific M2M Access Subscription Identifier;
obtaining an Access Point Name (APN) of an AN-based default M2M Network Services Capabilities (N-SC) application using the M2M Access Subscription Identifier, regardless of any other APN received from the M2M entity as part of the initial request;
connecting the M2M entity to the default M2M N-SC application using the APN of the AN default M2M N-SC; and
providing an M2M Service Layer (SL) initial registration of the M2M entity with the M2M SP network using the AN default M2M N-SC application.', 'receiving an initial request from the M2M entity to attach to the M2M SP network, wherein the initial request contains an entity-specific M2M Access Subscription Identifier;', 'obtaining an Access Point Name (APN) of an AN-based default M2M Network Services Capabilities (N-SC) application using the M2M Access Subscription Identifier, regardless of any other APN received from the M2M entity as part of the initial request;', 'connecting the M2M entity to the default M2M N-SC application using the APN of the AN default M2M N-SC; and', 'providing an M2M Service Layer (SL) initial registration of the M2M entity with the M2M SP network using the AN default M2M N-SC application.

2. The method of claim 1, wherein the M2M entity is one of the following:
an M2M Device; and
an M2M Gateway.', 'an M2M Device; and', 'an M2M Gateway.

3. The method of claim 1, wherein the M2M Access Subscription Identifier is at least one of the following:
International Mobile Subscriber Identity (IMSI) assigned to the M2M entity; and
Network Access Identifier (NAI) assigned to the M2M entity.', 'International Mobile Subscriber Identity (IMSI) assigned to the M2M entity; and', 'Network Access Identifier (NAI) assigned to the M2M entity.

4. The method of claim 1, wherein the step of obtaining the APN of the AN default M2M N-SC application includes:
using the M2M Access Subscription Identifier to access a corresponding entity-specific M2M Access Subscription profile in the AN, wherein the AN-based M2M Access Subscription profile contains the APN of the AN default M2M N-SC application; and
retrieving the APN of the AN default M2M N-SC application from the AN-based M2M Access Subscription profile, regardless of any APN received from the M2M entity as part of the initial request.', 'using the M2M Access Subscription Identifier to access a corresponding entity-specific M2M Access Subscription profile in the AN, wherein the AN-based M2M Access Subscription profile contains the APN of the AN default M2M N-SC application; and', 'retrieving the APN of the AN default M2M N-SC application from the AN-based M2M Access Subscription profile, regardless of any APN received from the M2M entity as part of the initial request.

5. The method of claim 4, further performing at least one of the following steps using the AN default M2M N-SC application:
updating the AN-based M2M Access Subscription profile with at least one of the following information:
an Across-Layers (A-Layers) M2M Identifier of the M2M entity received from the M2M SP network, and
the APN of an AN-based regular M2M N-SC application that serves the M2M entity-chosen M2M SP network;

updating an entity-based M2M Access Subscription in the M2M entity with at least one of the following information:
the A-Layers M2M Identifier of the M2M entity received from the M2M SP, and
the APN of the AN-based regular M2M N-SC application that serves the M2M entity-chosen M2M SP network; and

updating an AN-based M2M Access Policy Subscription of the M2M entity with application-specific Quality of Service (QoS) information for at least one M2M application supported on the M2M entity.', 'updating the AN-based M2M Access Subscription profile with at least one of the following information:
an Across-Layers (A-Layers) M2M Identifier of the M2M entity received from the M2M SP network, and
the APN of an AN-based regular M2M N-SC application that serves the M2M entity-chosen M2M SP network;', 'an Across-Layers (A-Layers) M2M Identifier of the M2M entity received from the M2M SP network, and', 'the APN of an AN-based regular M2M N-SC application that serves the M2M entity-chosen M2M SP network;', 'updating an entity-based M2M Access Subscription in the M2M entity with at least one of the following information:
the A-Layers M2M Identifier of the M2M entity received from the M2M SP, and
the APN of the AN-based regular M2M N-SC application that serves the M2M entity-chosen M2M SP network; and', 'the A-Layers M2M Identifier of the M2M entity received from the M2M SP, and', 'the APN of the AN-based regular M2M N-SC application that serves the M2M entity-chosen M2M SP network; and', 'updating an AN-based M2M Access Policy Subscription of the M2M entity with application-specific Quality of Service (QoS) information for at least one M2M application supported on the M2M entity.

6. The method of claim 5, wherein the entity-based M2M Access Subscription contains at least one of the following information:
whether the M2M entity is being used for M2M services only;
whether the M2M entity is being used for M2M services and Internet access; and
whether the M2M entity is being used for Internet access only.', 'whether the M2M entity is being used for M2M services only;', 'whether the M2M entity is being used for M2M services and Internet access; and', 'whether the M2M entity is being used for Internet access only.

7. The method of claim 1, wherein the step of providing the M2M SL initial registration includes:
the AN default M2M N-SC application receiving an M2M Services Subscription Identifier from the M2M entity;
from the received M2M Services Subscription Identifier, the AN default M2M N-SC application identifying the M2M entity-chosen M2M SP network and M2M services architecture supported by the M2M SP network with respect to the AN default M2M N-SC application; and
the AN default M2M N-SC application executing the M2M SL initial registration with the M2M SP based on the respective M2M services architecture.', 'the AN default M2M N-SC application receiving an M2M Services Subscription Identifier from the M2M entity;', 'from the received M2M Services Subscription Identifier, the AN default M2M N-SC application identifying the M2M entity-chosen M2M SP network and M2M services architecture supported by the M2M SP network with respect to the AN default M2M N-SC application; and', 'the AN default M2M N-SC application executing the M2M SL initial registration with the M2M SP based on the respective M2M services architecture.

8. The method of claim 7, wherein the step of executing the M2M SL initial registration includes:
the AN default M2M N-SC application receiving at least one of the following from the M2M SP:
an Across-Layers (A-Layers) M2M Identifier of the M2M entity;
an SC Identifier for Services Capabilities of the M2M entity; and
an identification of one or more M2M Application Identifiers associated with corresponding M2M applications supported on the M2M entity.', 'the AN default M2M N-SC application receiving at least one of the following from the M2M SP:
an Across-Layers (A-Layers) M2M Identifier of the M2M entity;
an SC Identifier for Services Capabilities of the M2M entity; and
an identification of one or more M2M Application Identifiers associated with corresponding M2M applications supported on the M2M entity.', 'an Across-Layers (A-Layers) M2M Identifier of the M2M entity;', 'an SC Identifier for Services Capabilities of the M2M entity; and', 'an identification of one or more M2M Application Identifiers associated with corresponding M2M applications supported on the M2M entity.', '9. The method of claim 1, wherein the step of providing the M2M SL initial registration includes:
providing the M2M SL initial registration of the M2M entity with an M2M SP N-SC using the AN default M2M N-SC application.', 'providing the M2M SL initial registration of the M2M entity with an M2M SP N-SC using the AN default M2M N-SC application.', '10. The method of claim 9, wherein the M2M SP N-SC is a server and the AN default M2M N-SC is a proxy that is configured to act on behalf of the M2M SP N-SC server, and wherein the step of providing the M2M SL initial registration includes:
the AN-based M2M N-SC proxy communicating SL signaling messages with the M2M SP N-SC server using M2M SL Application Program Interface (API) to facilitate the M2M SL initial registration of the M2M entity with the M2M SP N-SC server.', 'the AN-based M2M N-SC proxy communicating SL signaling messages with the M2M SP N-SC server using M2M SL Application Program Interface (API) to facilitate the M2M SL initial registration of the M2M entity with the M2M SP N-SC server.', '11. The method of claim 9, further comprising:
the AN default M2M N-SC application providing at least one of the identity and the reachability information of the M2M SP N-SC to the M2M entity;
the AN default M2M N-SC application instructing the M2M entity to update the AN default M2M N-SC application with Across-Layers (A-Layers) information after successful M2M SL initial registration with the M2M SP N-SC;
the AN default M2M N-SC application receiving the A-Layers information from the M2M entity; and
based on the received A-Layers information, the AN default M2M N-SC application performing an update of at least one of the following with the APN of a Packet Data Network Gateway (P-GW) in the AN that facilitates subsequent regular registration of the M2M entity with the M2M SP N-SC:
AN-based M2M Access Subscription of the M2M entity, and
an entity-based M2M Access Subscription stored on the M2M entity.', 'the AN default M2M N-SC application providing at least one of the identity and the reachability information of the M2M SP N-SC to the M2M entity;', 'the AN default M2M N-SC application instructing the M2M entity to update the AN default M2M N-SC application with Across-Layers (A-Layers) information after successful M2M SL initial registration with the M2M SP N-SC;', 'the AN default M2M N-SC application receiving the A-Layers information from the M2M entity; and', 'based on the received A-Layers information, the AN default M2M N-SC application performing an update of at least one of the following with the APN of a Packet Data Network Gateway (P-GW) in the AN that facilitates subsequent regular registration of the M2M entity with the M2M SP N-SC:
AN-based M2M Access Subscription of the M2M entity, and
an entity-based M2M Access Subscription stored on the M2M entity.', 'AN-based M2M Access Subscription of the M2M entity, and', 'an entity-based M2M Access Subscription stored on the M2M entity.', '12. The method of claim 9, further comprising:
the AN default M2M N-SC application providing at least one of the identity and the reachability information of the M2M SP N-SC to the M2M entity;
the AN default M2M N-SC application requesting the M2M SP N-SC to update the AN default M2M N-SC with Across-Layers (A-Layers) information after completion of M2M SL initial registration steps for the M2M entity but before the M2M SP N-SC informs the M2M entity of the success of the initial registration;
the AN default M2M N-SC application receiving the A-Layers information from the M2M SP N-SC;
based on the received A-Layers information, the AN default M2M N-SC application performing an update of at least one of the following with the APN of a Packet Data Network Gateway (P-GW) in the AN that facilitates subsequent regular registration of the M2M entity with the M2M SP N-SC:
AN-based M2M Access Subscription of the M2M entity, and
an entity-based M2M Access Subscription stored on the M2M entity; and

the AN default M2M N-SC application indicating success of the update to the M2M SP N-SC so as to enable the M2M SP N-SC to inform the M2M entity of the success of the M2M SL initial registration.', 'the AN default M2M N-SC application providing at least one of the identity and the reachability information of the M2M SP N-SC to the M2M entity;', 'the AN default M2M N-SC application requesting the M2M SP N-SC to update the AN default M2M N-SC with Across-Layers (A-Layers) information after completion of M2M SL initial registration steps for the M2M entity but before the M2M SP N-SC informs the M2M entity of the success of the initial registration;', 'the AN default M2M N-SC application receiving the A-Layers information from the M2M SP N-SC;', 'based on the received A-Layers information, the AN default M2M N-SC application performing an update of at least one of the following with the APN of a Packet Data Network Gateway (P-GW) in the AN that facilitates subsequent regular registration of the M2M entity with the M2M SP N-SC:
AN-based M2M Access Subscription of the M2M entity, and
an entity-based M2M Access Subscription stored on the M2M entity; and', 'AN-based M2M Access Subscription of the M2M entity, and', 'an entity-based M2M Access Subscription stored on the M2M entity; and', 'the AN default M2M N-SC application indicating success of the update to the M2M SP N-SC so as to enable the M2M SP N-SC to inform the M2M entity of the success of the M2M SL initial registration.', '13. The method of claim 1, wherein the step of receiving the initial request includes receiving at least one of the following from the M2M entity as part of the initial request:
a NULL APN; and
the APN of the AN-based default M2M N-SC application.', 'a NULL APN; and', 'the APN of the AN-based default M2M N-SC application.', '14. The method of claim 1, further comprising performing the following steps using the AN:
after the M2M SL initial registration, updating at least one of the following with a regular M2M N-SC APN that identifies an AN-based network element serving the M2M entity-chosen M2M SP network:
AN-based M2M Access Subscription of the M2M entity, and
an entity-based M2M Access Subscription stored on the M2M entity;

receiving a Regular Attach request from the M2M entity to re-attach to the M2M SP network;
establishing a 3GPP Packet Data Network (PDN) connection between the M2M entity and the AN-based network element using the regular M2M N-SC APN; and
providing an M2M SL regular registration of the M2M entity with the M2M SP network via the AN-based network element.', 'after the M2M SL initial registration, updating at least one of the following with a regular M2M N-SC APN that identifies an AN-based network element serving the M2M entity-chosen M2M SP network:
AN-based M2M Access Subscription of the M2M entity, and
an entity-based M2M Access Subscription stored on the M2M entity;', 'AN-based M2M Access Subscription of the M2M entity, and', 'an entity-based M2M Access Subscription stored on the M2M entity;', 'receiving a Regular Attach request from the M2M entity to re-attach to the M2M SP network;', 'establishing a 3GPP Packet Data Network (PDN) connection between the M2M entity and the AN-based network element using the regular M2M N-SC APN; and', 'providing an M2M SL regular registration of the M2M entity with the M2M SP network via the AN-based network element.', '15. The method of claim 14, wherein the AN-based network element includes one of the following:
a regular M2M N-SC server;
a regular M2M N-SC proxy; and
a Packet Data Network Gateway (P-GW).', 'a regular M2M N-SC server;', 'a regular M2M N-SC proxy; and', 'a Packet Data Network Gateway (P-GW).', '16. The method of claim 14, wherein the Regular Attach request from the M2M entity includes one of the following:
a NULL APN; and
the regular M2M N-SC APN.', 'a NULL APN; and', 'the regular M2M N-SC APN.', '17. The method of claim 14, wherein the step of establishing the 3GPP PDN connection includes:
retrieving the regular M2M N-SC APN from a Home Subscriber Server (HSS) in the AN.', 'retrieving the regular M2M N-SC APN from a Home Subscriber Server (HSS) in the AN.', '18. The method of claim 14, wherein the step of providing the M2M SL regular registration includes:
receiving from the M2M entity an Across-Layers (A-Layers) M2M Identifier of the M2M entity; and
using the A-Layers M2M Identifier of the M2M entity to identify the M2M entity and to determine reachability of the M2M entity during regular attachment of the M2M entity with the M2M SP network.', 'receiving from the M2M entity an Across-Layers (A-Layers) M2M Identifier of the M2M entity; and', 'using the A-Layers M2M Identifier of the M2M entity to identify the M2M entity and to determine reachability of the M2M entity during regular attachment of the M2M entity with the M2M SP network.', '19. A Third Generation Partnership Project (3GPP) Evolved Packet Core (EPC) based wireless Access Network (AN) to enable attachment of a Machine-to-Machine (M2M) entity to an M2M Service Provider (SP) network chosen by the M2M entity, wherein the AN is configured to perform the following:
receive an initial request from the M2M entity to attach to the M2M SP network, wherein the initial request contains an entity-specific M2M Access Subscription Identifier;
obtain an Access Point Name (APN) of an AN-based default M2M Network Services Capabilities (N-SC) application using the M2M Access Subscription Identifier, regardless of any other APN received from the M2M entity as part of the initial request;
connect the M2M entity to the default M2M N-SC application using the APN of the AN default M2M N-SC application; and
provide an M2M Service Layer (SL) initial registration of the M2M entity with the M2M SP network using the AN default M2M N-SC application.', 'receive an initial request from the M2M entity to attach to the M2M SP network, wherein the initial request contains an entity-specific M2M Access Subscription Identifier;', 'obtain an Access Point Name (APN) of an AN-based default M2M Network Services Capabilities (N-SC) application using the M2M Access Subscription Identifier, regardless of any other APN received from the M2M entity as part of the initial request;', 'connect the M2M entity to the default M2M N-SC application using the APN of the AN default M2M N-SC application; and', 'provide an M2M Service Layer (SL) initial registration of the M2M entity with the M2M SP network using the AN default M2M N-SC application.

20. The AN of claim 19, further configured to perform the following:
after the M2M SL initial registration, update at least one of the following with a regular M2M N-SC APN that identifies an AN-based network element serving the M2M entity-chosen M2M SP network:
AN-based M2M Access Subscription of the M2M entity, and
an entity-based M2M Access Subscription stored on the M2M entity;

receive a Regular Attach request from the M2M entity to re-attach to the M2M SP network;
establish a 3GPP connection between the M2M entity and the AN-based network element using the regular M2M N-SC APN; and
provide an M2M SL regular registration of the M2M entity with the M2M SP network via the AN-based network element.', 'after the M2M SL initial registration, update at least one of the following with a regular M2M N-SC APN that identifies an AN-based network element serving the M2M entity-chosen M2M SP network:
AN-based M2M Access Subscription of the M2M entity, and
an entity-based M2M Access Subscription stored on the M2M entity;', 'AN-based M2M Access Subscription of the M2M entity, and', 'an entity-based M2M Access Subscription stored on the M2M entity;', 'receive a Regular Attach request from the M2M entity to re-attach to the M2M SP network;', 'establish a 3GPP connection between the M2M entity and the AN-based network element using the regular M2M N-SC APN; and', 'provide an M2M SL regular registration of the M2M entity with the M2M SP network via the AN-based network element.

21. A Machine-to-Machine (M2M) entity configured to communicate with an M2M Service Provider (SP) network via a Third Generation Partnership Project (3GPP) Evolved Packet Core (EPC) based wireless Access Network (AN), the M2M entity comprises:
a memory configured to store an M2M Access. Subscription Identifier of the M2M entity; and
a processor coupled to the memory and configured to perform the following:
send an initial request to the AN to attach to the M2M SP network, wherein the initial request contains the M2M Access Subscription Identifier,
connect to an AN-based default M2M Network Services Capabilities (N-SC) application using an Access Point Name (APN) thereof, regardless of any other APN sent by the processor to the AN as part of the initial request, and
perform an M2M Service Layer (SL) initial registration of the M2M entity with the M2M SP network using the AN default M2M N-SC application.', 'a memory configured to store an M2M Access. Subscription Identifier of the M2M entity; and', 'a processor coupled to the memory and configured to perform the following:
send an initial request to the AN to attach to the M2M SP network, wherein the initial request contains the M2M Access Subscription Identifier,
connect to an AN-based default M2M Network Services Capabilities (N-SC) application using an Access Point Name (APN) thereof, regardless of any other APN sent by the processor to the AN as part of the initial request, and
perform an M2M Service Layer (SL) initial registration of the M2M entity with the M2M SP network using the AN default M2M N-SC application.', 'send an initial request to the AN to attach to the M2M SP network, wherein the initial request contains the M2M Access Subscription Identifier,', 'connect to an AN-based default M2M Network Services Capabilities (N-SC) application using an Access Point Name (APN) thereof, regardless of any other APN sent by the processor to the AN as part of the initial request, and', 'perform an M2M Service Layer (SL) initial registration of the M2M entity with the M2M SP network using the AN default M2M N-SC application.

22. The M2M entity of claim 21, wherein the memory is further configured to store at least one of the following:
entity-specific M2M Services Capabilities (SC);
one or more M2M applications;
an M2M Services Subscription Identifier identifying the M2M SP network and M2M services architecture supported by the M2M SP network;
an M2M Access Subscription associated with the M2M Access Subscription Identifier;
the APN of the AN-based default M2M N-SC application;
a Null APN,
a regular M2M N-SC APN that identifies an AN-based network element serving the M2M SP network;
an Across-Layers (A-Layers) M2M Identifier of the M2M entity to identify the M2M entity and to determine reachability of the M2M entity;
identity and the reachability information of an M2M SP N-SC; and
security credentials of the M2M entity.', 'entity-specific M2M Services Capabilities (SC);', 'one or more M2M applications;', 'an M2M Services Subscription Identifier identifying the M2M SP network and M2M services architecture supported by the M2M SP network;', 'an M2M Access Subscription associated with the M2M Access Subscription Identifier;', 'the APN of the AN-based default M2M N-SC application;', 'a Null APN,', 'a regular M2M N-SC APN that identifies an AN-based network element serving the M2M SP network;', 'an Across-Layers (A-Layers) M2M Identifier of the M2M entity to identify the M2M entity and to determine reachability of the M2M entity;', 'identity and the reachability information of an M2M SP N-SC; and', 'security credentials of the M2M entity.

23. The M2M entity of claim 21, wherein the processor is further configured to perform the following as part of connecting to the AN default M2M N-SC application:
establish a 3GPP Packet Data Network (PDN) connection between the M2M entity and the AN default M2M N-SC application using the APN of the AN default M2M N-SC application.', 'establish a 3GPP Packet Data Network (PDN) connection between the M2M entity and the AN default M2M N-SC application using the APN of the AN default M2M N-SC application.

24. The M2M entity of claim 21, wherein the processor is further configured to perform the following:
after the M2M SL initial registration, send a Regular Attach request to the AN to re-attach to the M2M SP network;
establish a 3GPP Packet Data Network (PDN) connection between the M2M entity and an AN-based network element serving the M2M SP network; and
perform an M2M SL regular registration of the M2M entity with the M2M SP network via the AN-based network element.', 'after the M2M SL initial registration, send a Regular Attach request to the AN to re-attach to the M2M SP network;', 'establish a 3GPP Packet Data Network (PDN) connection between the M2M entity and an AN-based network element serving the M2M SP network; and', 'perform an M2M SL regular registration of the M2M entity with the M2M SP network via the AN-based network element.']