PCRF/PCF Redundancy for Seamless Session Establishment After Link Failure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In LTE and 5G wireless communication networks, redundant deployment of Policy and Charging Rules Function (PCRF) or Policy Control Function (PCF) nodes is used to enhance reliability, but failures lead to excessive delays in session establishment due to the need for users to reinitiate sessions when link failures occur, impacting user experience.
Innovation Solution
Implement techniques that allow a failed PCRF/PCF node to notify another node of a temporary failure, enabling seamless session continuation without reinitiation by using customized messages like Error-Message AVPs, allowing the alternative node to complete the session establishment process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If redundant deployment of PCRF/PCF nodes is implemented, then reliability is improved, but session establishment delay increases when link failures occur
Solution Approach 1:
The patent applies preliminary action by having the Application Function (AF) proactively select and establish communication links with multiple PCRF/PCF nodes (primary and secondary) before failures occur. When a link failure is detected, the AF can immediately switch to the pre-established secondary link without needing to reinitiate the entire session establishment process, thus resolving the contradiction between reliability improvement and time loss.
2Reliability
If users reinitiate sessions after link failures, then session continuity is maintained, but user experience deteriorates due to excessive delays
Solution Approach 1:
The patent introduces the Application Function (AF) as an intermediary that monitors link status between the UE and PCRF/PCF nodes. When a link failure occurs, the AF detects it and triggers a seamless handover to a secondary PCRF/PCF node without requiring user action or session reinitiation. This intermediary mechanism maintains session continuity while preserving user experience by eliminating the need for users to manually reinitiate sessions.
3Ease of operation
If seamless session continuation is implemented, then user experience is improved, but device complexity increases due to multiple communication links
Solution Approach 1:
The patent implements self-service by enabling the AF to autonomously monitor link status, detect failures, and perform handovers between primary and secondary PCRF/PCF nodes without requiring complex user device involvement. The network side (AF) handles the complexity of managing multiple communication links, while the user device (UE) experiences seamless session continuation. This shifts the complexity burden from the user device to the network infrastructure.
Data Source
AI summary
Systems, methods, and devices that relate to reducing or minimizing session establishment delay with redundant deployment of policy control nodes are disclosed. In one example aspect, a method for wireless communication includes receiving, by a first communication node configured to provide policy control in a communication network, a request for establishing a communication session with a mobile device. The method also includes determining, by the first communication node, that a failure has occurred between the first communication node and a second communication node for establishing the communication session, and transmitting, by the first communication node, a notification to a third communication node indicating information about the failure.