Core SCEF/MTC-IWF

Core SCEF/MTC-IWF implements the business logic of different MTC functional call procedures specific to SCEF and MTC-IWF network elements. Core SCEF/MTC-IWF interfaces with the API gateway to send or receive the T8 requests from SCS/AS.

DSR has implemented the following MTC functional procedures of SCEF/MTC-IWF network elements.

• Non-IP Data Delivery (NIDD) provides a path to exchange unstructured data between UE and SCS/AS without requiring the user equipment (UE) to support an IP stack.

  Eliminating the need to support IP results in the following benefits:

  • Reduces device complexity since there is no need to support TCP/IP
  • Reduces device cost due to lower complexity
  • Reduces device power consumption due to eliminating extra messaging and overhead related to TCP/IP
  • Compatibility with older devices not supporting IP

  NIDD, using the SCEF, is handled using a PDN connection to the SCEF. The UE may obtain a non-IP PDN connection to the SCEF during the attach procedure; using UE requested PDN; or using the PDP context activation procedure. An association between the SCS/AS and a PDN connection to the SCEF needs to be established to enable transfer of non-IP data between the UE and the SCS/AS. The SCEF determines the association based on provisioned policies that may be used to map an SCS/AS identity and user identity to an access point name (APN). SCEF supports both mobile terminated (MT) and mobile originated (MO) NIDD communication between UE and SCS/AS.

• The Monitoring Events feature monitors specific events in the 3GPP system and makes monitoring events information available through SCEF. This means you can identify the 3rd Generation Partnership Project (3GPP) network element suitable for configuring specific events, event detection, and event reporting to the authorized users, for example, for use by applications or logging. If such an event is detected, the network might be configured to perform special actions, for example, limit UE access.

  DSR supports the following monitoring events configuration and deletion using HSS:

  • LOSS_OF_CONNECTIVITY

    Notifies the AS when the UE loses connection and becomes offline, which signals device abnormality and need for troubleshooting.

  • UE_REACHABILITY

    Allows AS to know the status of the devices as reachable or not reachable.

  • LOCATION_REPORTING

    Allows the AS (enterprise) to track the location of the devices without GPS modules (cargo tracking).

  • CHANGE_OF_IMSI_IMEI(SV)_ASSOCIATION

    Allows AS to detect stolen devices.

  • ROAMING_STATUS

    Allows the SCS/AS to query the UE's current roaming status (the serving public land mobility network (PLMN) and/or whether the UE is in its home PLMN (HPLMN)) and notifies when that status changes.

  • UE_REACHABILITY

    Allows AS to know the status of the devices as reachable or not reachable with a status flag (idleStatusIndication flag = true).

  DSR supports both a single report event and a continuous event report for the requested monitoring events from SCS/AS. DSR supports both monitoring requests for a group of UE or single UE.

• The Enhanced Coverage Restriction Control enables 3rd party service providers (that is, SCS/AS) to query status, enhance coverage restriction, or enable/disable enhanced coverage restriction per individual UE.
• The Device Triggering feature allows the SCS/AS to deliver a specific device trigger to the UE through SCEF. The Device Trigger request is authenticated with HSS using the User Identifier received in the request. After successful authentication, SCEF forwards the Device Trigger request to the corresponding SMS-SC to be delivered to the UE.