The present document investigates possible enhancements of the Diameter base protocol (IETF RFC 6733 [2] and existing Diameter applications to support overload control mechanisms in 3GPP core networks. This work is based on the results of the feasibility study on Core Network Overload available in TR 23.843 and the related work done in the IETF Diameter Maintenance and Extensions (DiME) working group. This study will cover:

• Identification of the set of requirements for an improved overload control mechanism over Diameter based signaling interfaces used in 3GPP core networks.
• Identification, evaluation and selection of candidate solutions for overload control mechanisms, including:
  • Mechanisms to detect overload situations e.g. notification of Diameter end-point signaling load;
  • Mechanisms to exchange overload control policies between Diameter end-points;
  • Details on the expected behaviour of 3GPP core network nodes supporting the defined overload control mechanism (Diameter end-points and Diameter agent);
  • Evaluation of the impacts of the proposed solution(s) on existing Diameter-based Technical Specifications and Diameter based signalling networks (internal operator networks, inter-operator network (e.g. IPX).
  • Recommendations on the solutions to select depending of the applicability context (interfaces, application, network, etc.)

The results of this study will contribute to the work done within the IETF DiME working group on Diameter overload control, through official liaison statement from 3GPP or company-driven individual contributions, which includes:

• Provide feedback from 3GPP on the requirements for Diameter overload control mechanisms defined in IETF Draft draft-ietf-dime-overload-reqs-06 [4]);
• Contribute to the specification of the IETF standard mechanism for overload control over Diameter.

The results of this study will be used to identify the changes required in the 3GPP specifications to support overload control mechanisms over Diameter-based 3GPP interfaces and applications.