AUSF Selection for Synchronized 5G Application Session Keys
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 5G networks, there are challenges in synchronizing key material generated by an Authentication Server Function (AUSF) with the key material used by an Anchor Function for authentication and key management (AAnF) to establish secure communication between user applications and application functions, leading to difficulties in establishing secure application sessions.
Innovation Solution
A key management server (AAnF) facilitates the determination and generation of application-specific security keys by identifying the AUSF that generated the non-application-specific anchor security key, using identifiers and network repository functions to synchronize key materials, and interacting with the Unified Data Management (UDM) to ensure secure communication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an AUSF generates non-application-specific anchor security key material, then authentication capability is provided, but synchronization with AAnF key material becomes difficult
Solution Approach 1:
The patent introduces an intermediary mechanism (the AUSF identification and key material retrieval process) that mediates between the key generation function of the AUSF and the key usage function of the AAnF. The AAnF identifies the specific AUSF that generated the anchor security key and retrieves the corresponding key material from that AUSF, ensuring synchronization without requiring direct continuous communication between all components.
Solution Approach 2:
The patent implements a feedback mechanism where the AAnF receives information about which AUSF generated the anchor security key and uses this feedback to retrieve the correct key material. The process includes receiving an indication of the AUSF, retrieving key material from that specific AUSF, and using it in the AAnF, creating a closed-loop system that ensures key synchronization.
2Reliability
If key material is generated and stored in AUSF, then security key management is enabled, but access to key material by AAnF becomes complex
Solution Approach 1:
The patent uses the AUSF itself as an intermediary storage and distribution point for key material. Instead of requiring the AAnF to directly access multiple storage locations or complex key management systems, the AAnF requests key material from the identified AUSF, which then provides the appropriate key material. This simplifies the access process while maintaining secure key management.
Solution Approach 2:
The AUSF serves itself by storing and managing its own generated key material, and also serves the AAnF by providing this key material upon request. The system leverages the existing AUSF infrastructure to handle key distribution, eliminating the need for separate key management storage and access mechanisms.
Data Source
AI summary
Embodiments include methods performed by a key management node in a communication network. Such methods can include receiving, from an application function, a request for a security key specific to an application session for a particular user. The request can include a representation of the following information associated with the particular user: a first identifier of a non-application-specific anchor security key, and a second identifier related to a network subscription. Such methods can also include, based on the representation, determining an authentication server function that generated the non-application-specific anchor security key. Other embodiments include complementary methods performed by application functions, authentication server functions, and unified data management functions in the communication network. Other embodiments include network nodes configured to perform such methods.