IAB Network Rerouting via Unified BAP Addressing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current 3GPP Rel-16 specifications for Integrated Access Backhaul (IAB) networks face challenges in rerouting traffic effectively across different donor DUs, leading to packet loss and suboptimal network load balancing due to limitations in using BAP addresses and routing IDs during backhaul link failures and congestion.
Innovation Solution
The proposed solution involves assigning the same BAP destination address to all donor DUs under a donor CU, allowing intermediate IAB nodes to reroute packets using a larger set of paths terminating at all donor DUs, and configuring dedicated BH RLC channels for rerouted traffic, enabling inter-donor DU rerouting and enhancing network load balancing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the same BAP destination address is assigned to all donor DUs under a donor CU, then packet loss is minimized and network robustness is improved, but device complexity increases due to additional routing configuration
Solution Approach 1:
The patent applies universality by assigning the same BAP destination address to all donor DUs under a donor CU, enabling intermediate IAB nodes to use a unified addressing scheme for routing packets to multiple donor DUs. This multi-functional address assignment allows the network to handle both normal and rerouted traffic through a single address space, improving reliability without requiring separate addressing mechanisms for different traffic types.
Solution Approach 2:
The patent introduces the BAP routing ID as an intermediary element that mediates between the unified BAP destination address and the specific donor DU selection. The BAP routing ID acts as a discriminator that enables intermediate nodes to differentiate between multiple donor DUs sharing the same destination address, allowing effective routing decisions while maintaining address uniformity across the network.
2Productivity
If intermediate IAB nodes use a larger set of paths terminating at all donor DUs, then network load balancing is improved, but the difficulty of detecting and measuring routing states increases
Solution Approach 1:
The patent segments the routing decision process into two distinct parts: the BAP destination address that identifies the target donor DU group, and the BAP routing ID that specifies the particular path or donor DU within that group. This segmentation allows intermediate IAB nodes to independently manage multiple paths to different donor DUs, enabling effective load balancing while simplifying routing state detection through clear hierarchical addressing.
3Reliability
If dedicated BH RLC channels are configured for rerouted traffic, then packet loss is reduced during backhaul link failures, but device complexity increases due to additional channel configuration
Solution Approach 1:
The patent applies preliminary action by pre-configuring dedicated Backhaul Radio Link Control (BH RLC) channels for rerouted traffic before actual link failures occur. These dedicated channels are established in advance as backup paths, enabling immediate traffic redirection when primary backhaul links fail, thereby reducing packet loss. The F1 interface is configured with alternative routing paths that can be activated without complex real-time decision-making during failure events.
Data Source
AI summary
A method performed by a first donor distributed unit (DU) in an integrated access backhaul (IAB) network is provided. The method includes obtaining for each IAB node under the domain of each donor DU in the IAB network, a respective assigned IP address of the respective IAB node, receiving a rerouted packet, checking whether a source IP address of the rerouted packet matches an assigned IP address of an IAB node under the domain of the first donor DU, if the source IP address does not match an assigned IP address of an IAB node under the domain of the first donor DU, checking whether the source IP address of the rerouted packet matches an assigned IP address obtained by the donor DU, and if the source IP address matches an assigned IP address obtained the donor DU, forwarding the rerouted packet to an upper layer.