Anchor Node End Markers for 5G Handover Packet Ordering

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current 5G wireless communication networks face inefficiencies during handover procedures due to the lack of clear indication of the last packet from multiple anchor network nodes, leading to potential packet loss and reordered delivery.

Innovation Solution

Implementing a method where every anchor network node involved in a session sends an end marker, allowing the receiving node to determine when all packets have been received and ensuring lossless, in-order delivery by comparing the number of received end markers to the number of nodes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple anchor network nodes route data packets during handover, then packet delivery coverage is improved, but packet ordering and loss control deteriorates

Engineering Contradiction:
Improvepacket delivery coverageVSAvoidpacket ordering and loss control
Core Design Contradiction:
ReliabilityVSLoss of information

Solution Approach 1:

The patent segments the handover process by introducing distinct end marker packets for each anchor network node. Each anchor node sends its own end marker to indicate when it has finished transmitting packets, allowing the target base station to track and manage packets from multiple sources independently. This segmentation enables precise control over packet ordering and loss prevention while maintaining multi-node routing coverage.

Inventive Principle:
Principle #1Segmentation

2Device complexity

If end markers are sent from only one anchor network node, then signaling overhead is reduced, but packet loss detection becomes unreliable

Engineering Contradiction:
Improvesignaling overheadVSAvoidpacket loss detection
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent applies local quality by making each anchor network node send its own end marker packet specific to its data transmission. Instead of a single centralized end marker, each anchor node (e.g., UPF-A, UPF-B) generates and sends its own end marker when it finishes transmitting packets. This localized approach ensures that packet loss detection is reliable for each individual anchor node's contribution while keeping the overall system manageable.

Inventive Principle:
Principle #3Local quality

3Reliability

If extensive buffering is implemented to ensure in-order delivery, then packet delivery reliability is improved, but network latency increases

Engineering Contradiction:
Improvepacket delivery reliabilityVSAvoidnetwork latency
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent implements preliminary action by having anchor network nodes send end marker packets in advance or concurrently with data packets. The target base station receives end markers that indicate the completion status of packet transmission from each anchor node, allowing it to proactively manage buffering and forwarding decisions. This preliminary indication mechanism reduces the need for extensive post-arrival buffering and minimizes latency while ensuring in-order delivery.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3918840B1Methods and network nodes for handling a session comprising data packets to be transmitted to a wireless device
Publication Date: 2023.11.15 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
  • EP3918840B1 patent drawingFigure 1
  • EP3918840B1 patent drawingFigure 2
  • EP3918840B1 patent drawingFigure 3~5

AI summary

Disclosed is a method performed by a network node (130, 140, 160) of a wireless communication network (100) comprising a first (130) and a second (140) core network node and a first (150) and a second (160) base station (150). A session of a wireless device (170) comprises data packets routed via a plurality of anchor network nodes (115, 120) from a data network (110).In connection with the wireless device (170) handing over from the first base station (150) and the first core network node (130) to the second base station (160) and the second core network node (140), the method comprises receiving information of the number of the plurality of anchor network nodes (115, 120) via which data packets of the session are routed, receiving data packets from the plurality of anchor network nodes (115, 120), receiving an end marker of each of the plurality of anchor network nodes (115, 120), each end marker indicating a last data packet of one of the plurality of anchor network nodes routed via the first core network node (130), and when the number of received end markers equals the number of the plurality of anchor network nodes, triggering to send to the wireless device (170) any data packets related to the session not routed via the first base station stored in a buffer of the second base station.