6.3 UE Attach with oneM2M Registration Procedure

After a UE attaches to an underlying 3GPP network and establishes a data (i.e. PDN/PDP) connection, assuming it has not been registered previously with the oneM2M platform, it will initiate a oneM2M registration procedure. The oneM2M part of the procedure corresponds to the generic one described in clause 10.2.2 of oneM2M TS-0001[1], where the Registrar CSE is the CSE (SCS).

If the UE hosts one or more ADNs, the registration will result in the CSE (SCS) hosting one or more corresponding <AE> resources for the UE. If the UE hosts an ASN or a MN, the registration of the ASN/MN-CSE will result in the CSE (SCS) hosting a corresponding <remoteCSE> resource for the ASN/MN-CSE. The flow is depicted in figure 6.3-1.

Figure 6.3-1: UE Attach Procedure with oneM2M Registration

Figure 6.3-1 UE Attach Procedure with oneM2M Registration

Steps 1a and 1b: UE Attach Request and Response

The UE determines that it needs to perform the 3GPP Attach procedure.

The underlying 3GPP Network responds to the UE Attach request.

Steps 2a and 2b : oneM2M Registration Request and Response

The UE Hosting an ADN or an ASN/MN registers to the oneM2M infrastructure, by performing the registration procedure detailed in clause 10.2.2 of oneM2M TS-0001[1].

  • If the UE hosts an ADN, the registration procedure of the ADN-AE(s) will include the creation of corresponding <AE> resource(s) being hosted at the CSE (SCS).
  • If the UE hosts an ASN or MN, the registration procedure of the ASN/MN-CSE will include the establishment of a security association and the creation of a <remoteCSE> resource, corresponding to the registree CSE, to be hosted at the CSE (SCS).

The CSE (SCS) responds to the UE hosted ADN-AE(s) or ASN/MN-CSE request for registration.

These steps allow the UE hosted ADN-AE(s) or ASN/MN-CSE to provide the CSE (SCS) with information needed for communication and providing services, e.g. pointOfAccess. In return, the CSE (SCS) provides the UE with oneM2M specific information, e.g. by assigning AE-ID(s) or CSE-ID to the registree(s), respectively

Information provided by the ASN/MN-CSE or ADN-AE(s) to the CSE (SCS) at this time shall include:

  • M2M-Ext-ID, Trigger-Recipient-ID as attributes of <AE> or <remoteCSE>, if available.
  • externalGroupID as an attribute of <AE> or <remoteCSE>, if available. nodeLink as an attribute of the <AE> or <remoteCSE> resources, providing the resource identifier of a corresponding <node> resource, if pre-provisioned at the UE.

Step 3 : Handling of association with a <node> resource

If in Step 2, the CSE (SCS) receives a valid nodeLink (as an attribute of the <AE> or <remoteCSE> resources) it means that the <node> resource storing the node specific information for this UE exists. For a UE hosted ASN/MN, the CSE (SCS) shall ensure that the hostedCSELink attribute of the corresponding <node> resource contains the resource identifier of the <remoteCSE> resource. For a UE hosted ADN, the CSE (SCS) shall ensure that the hostedAELinks attribute of the corresponding <node> resource includes the resource identifier of all the corresponding <AE> resources.

If in Step 2, the CSE (SCS) does not receive a valid nodeLink (as an attribute of the <AE> or <remoteCSE> resources) or the attribute is not present, the CSE (SCS) shall create a <node> resource for this UE. The CSE (SCS) shall populate the nodeLink attribute of the <AE> or <remoteCSE> resources with the resource identifier of the newly created <node> resource. For a UE hosted ASN/MN, the CSE (SCS) shall also populate the hostedCSELink attribute of the <node> resource with the resource identifier of the <remoteCSE> resource. For a UE hosted ADN, the CSE (SCS) shall ensure that the hostedAELinks attribute of the <node> resource includes the resource identifiers of all the corresponding <AE> resources.

If the following resources do not exist for this underlying 3GPP network, the CSE (SCS) may:

  • create a <schedule> resource as a child of the <node> representing the UE, which represents the communication schedule for the underlying 3GPP network where the Attach procedure was completed. While no specific scheduling information is available, the <schedule> may reflect that communications are available continuously. The CSE (SCS) may set the networkCoordinated attribute, based on the UE pre-provisioned information or local policies, to indicate if the schedule should be coordinated with the underlying 3GPP network
  • create the [activeCmdhPolicy] resource as a child of the <node> resource representing the UE, providing the active communication policies for the underlying 3GPP network where the Attach procedure was completed. The CSE (SCS) shall populate the mgmtLink of the active [cmdhNwAccessRule] with a link to the <schedule> resource created for the communication schedule with this underlying 3GPP network.