LTE Handover Tunnel Endpoint Identification for Call Preservation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication networks, particularly in LTE and other 3G+, 4G networks, handover scenarios between base stations or nodes often fail due to incorrect tunnel endpoint identification, leading to dropped calls or packets when the target node is connected to a different gateway than the source node.
Innovation Solution
The method involves passing the uplink tunnel endpoint from the source node to the target node, which then passes this value in an S1AP Path Switch message to the HeNBGW, allowing the HeNBGW to establish the correct GTP tunnel and return an acknowledgement, ensuring the handover request is successful by establishing the correct tunnel endpoints.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If handover is performed between base stations connected to different gateways, then mobile device connectivity is maintained during movement, but tunnel endpoint identification fails causing dropped calls or packets
Solution Approach 1:
The source base station performs preliminary actions by determining the gateway identifier before handover and including it in the handover request message sent to the target base station. This advance preparation ensures the target base station receives the correct gateway identification information needed to establish proper GTP tunnels, preventing tunnel endpoint identification failures during the handover process
Solution Approach 2:
The gateway identifier acts as an intermediary element that bridges the source and target base stations connected to different gateways. By passing this identifier through the handover request message, the system enables the target base station to correctly identify and connect to the appropriate gateway, resolving the tunnel endpoint identification problem in inter-gateway handover scenarios
2Device complexity
If traditional handover procedure is used without gateway identifier transmission, then handover process is simple, but tunnel establishment fails when target node connects to different gateway
Solution Approach 1:
The source base station determines the gateway identifier in advance and includes it in the handover request message. This preliminary inclusion of gateway identification information allows the target base station to establish GTP tunnels correctly without requiring complex additional signaling or procedures, thus maintaining procedural simplicity while improving tunnel establishment reliability
Solution Approach 2:
The gateway identifier serves as a mediating information element that enables correct tunnel establishment between base stations connected to different gateways. By transmitting this identifier through the existing handover request message, the invention avoids complicating the handover procedure while ensuring reliable tunnel establishment at the target node
Data Source
AI summary
In an example, a wireless communication system and apparatuses thereof are described. In an example long-term evolution (LTE) network, a first base station hands over a connection to a second base station. The first base station may be a (femto) home eNodeB (HeNB) or (macro) eNodeB. The second base station may also be a HeNB or eNodeB connected to a different gateway. The first base station may send “Handover Request” on an X2 connection, identifying the gateway that the second base station is connected to as the correct gateway. After sending a “Handover Request Acknowledgement,” the second base station correctly establishes a tunnel to a connected gateway device.