X2AP Neighbor Blocking Based on Load and Handover Activity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication networks, source eNodeBs attempt to establish X2AP connections with target eNodeBs that have reached their maximum connection capacity, leading to SCTP notification flooding due to unawareness of the target eNodeB's overload condition, which existing solutions like increasing SCTP retry timers fail to address effectively.
Innovation Solution
A network controller, such as an O-RAN RIC, monitors neighbor link counts and handover requests, blocking eNBs with low handover thresholds to prevent SCTP notification flooding by managing X2AP connections based on load conditions, and unblocking them when load criteria are met.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If the SCTP retry timer is increased to reduce notification flooding, then the flooding of SCTP notifications is reduced, but the SCTP association will not be retried for a long time (e.g., 5 minutes) even when the target eNB becomes unloaded, causing delayed connection establishment
Solution Approach 1:
The patent implements dynamic blocking and unblocking of X2AP neighbors based on real-time load conditions. The source eNB continuously monitors the target eNB's connection status and handover success rate, adjusting the blocking state accordingly. When the target eNB is overloaded, the source eNB blocks the neighbor to prevent flooding; when the load decreases, the block is removed to allow connection attempts, thus dynamically adapting to changing conditions rather than using a fixed retry timer
Solution Approach 2:
The patent employs feedback mechanisms where the source eNB monitors handover request outcomes and connection status between eNBs. Based on this feedback information (handover success rate, current connection count), the system automatically adjusts its behavior by blocking or unblocking neighbors, creating a closed-loop control system that responds to actual network conditions rather than relying on predetermined timer values
2Productivity
If the source eNB continuously attempts to connect to the target eNB after SCTP retry timer expiry, then connection establishment is pursued actively, but SCTP notification flooding occurs on the northbound interface
Solution Approach 1:
The patent applies preliminary anti-action by proactively blocking the target eNB in the source eNB's neighbor list before connection attempts are made when the target is known to be overloaded. The source eNB monitors the target's connection count and handover success rate in advance, and when thresholds are exceeded, it pre-blocks the neighbor to prevent subsequent flooding of connection attempts and SCTP notifications, thereby preventing the harmful effect before it occurs
Data Source
AI summary
A method comprises receiving a message including neighbor connection information regarding a number of connections between a target base station and one or more neighboring base stations. The method includes determining whether a connection condition is satisfied. The method comprises, in response to determining the connection condition is satisfied, determining a number of handover requests performed between the target base station and each of the one or more neighboring base stations. The method comprises placing each base station from the one or more neighboring base stations having a number of handover requests below a handover threshold on a list associated with blocking the target base station. The method further comprises transmitting, to each base station included on the list, a control request to block the target base station from receiving a connection request or handover request from a respective base station included on the list.