AMF NSSAA Retry Logic for HTTP 504 Gateway Timeout Handling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, Network Slice-Specific Authentication and Authorization (NSSAA) failures due to network errors or timeouts make it difficult for User Equipment (UE) to determine the cause of failure and restart the process, leading to challenges in data transmission and network slice re-authentication.
Innovation Solution
An Access and Mobility Management Function (AMF) method is implemented to initiate the NSSAA procedure for Single Network Slice Selection Assistance Information (S-NSSAI) with a Network Slice-Specific Authentication and Authorization Function (NSSAAF), and upon receiving an HTTP status code '504 Gateway Timeout' or no response, the AMF waits and then re-initiates the NSSAA procedure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the NSSAA procedure is initiated with NSSAAF for S-NSSAI, then network slice authentication and authorization can be performed, but network errors or timeouts may cause procedure failure making it difficult to determine the cause and restart the process
Solution Approach 1:
The AMF implements a feedback mechanism by monitoring response status from NSSAAF and implementing a retry logic with explicit failure cause identification. When the NSSAA procedure fails, the AMF determines the failure cause (network error vs timeout) and initiates appropriate retry actions, creating a closed-loop control system that improves reliability while maintaining operational clarity
Solution Approach 2:
The system performs preliminary error classification before retrying the NSSAA procedure. The AMF categorizes failures into network errors and timeouts, and prepares appropriate retry strategies in advance. This preliminary action enables the system to respond more effectively to different failure modes without ad-hoc decision-making during the retry process
2Reliability
If the AMF waits and re-initiates the NSSAA procedure after timeout, then service continuity can be maintained, but transmission time is increased due to waiting period
Solution Approach 1:
The AMF implements periodic retry attempts for the NSSAA procedure after timeout. Instead of a single wait period, the system performs multiple periodic retry attempts at defined intervals, balancing service continuity with time efficiency. This periodic approach allows the system to recover from transient failures while limiting the total time loss
Solution Approach 2:
The system dynamically adjusts the waiting period and retry parameters based on the specific timeout scenario. By modifying the retry interval and maximum retry count parameters, the AMF optimizes the balance between maintaining service continuity and minimizing transmission time delay for different network conditions
Data Source
AI summary
Provided are a method and a device for processing a network slice-specific authentication and authorization (NSSAA) failure caused by a network error or timeout. An access and mobility management function (AMF): starts an NSSAA procedure for an NSSAA function (NSSAAF) and single network slice selection assistance information (S-NSSAI); and restarts the NSSAA procedure after waiting for a certain period, on the basis that the Hypertext Transfer protocol (HTTP) status code “504 Gateway Timeout” is received from the NSSAAF, and/or a response regarding the NSSAA procedure could not be received from the NSSAAF.