Layered Missing Packet Detection for PDCP-RLC Loss Mismatch
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Layered missing packets in electronic devices, where a packet is lost at a higher layer without a corresponding loss at a lower layer, cause increased memory consumption and latency due to unnecessary reordering and buffering, as existing systems fail to detect and address these unbalanced packet losses.
Innovation Solution
Implementing layered missing packet detection methods that utilize sequence number comparisons and operations such as stopping reordering timers, adjusting sequence numbers, and flushing packets to mitigate the effects of layered missing packets, particularly at the PDCP layer without corresponding actions at the RLC layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If reordering and buffering procedures are performed for all packet losses, then packet delivery reliability is improved, but memory consumption and latency increase when losses are unbalanced across layers
Solution Approach 1:
The patent applies local quality by making the reordering and buffering operations selective rather than universal. Specifically, the PDCP layer performs reordering only when there is a corresponding missing packet at the RLC layer. When packet loss is unbalanced (missing at PDCP but not at RLC), the system skips the reordering operation locally at the PDCP layer, thereby avoiding unnecessary latency while maintaining reliability for cases where reordering is actually needed.
2Reliability
If reordering and buffering procedures are performed for all packet losses, then packet delivery reliability is improved, but memory consumption increases due to unnecessary buffering
Solution Approach 1:
The patent implements local quality by making buffering operations conditional on the detection of corresponding missing packets at both layers. The PDCP layer buffers packets only when the RLC layer also reports missing packets, creating a localized response that matches the actual loss pattern. This prevents unnecessary memory consumption while maintaining the buffering capability when it is truly needed for reliability.
Solution Approach 2:
The patent applies partial action by performing reordering and buffering only for the subset of packet losses that are unbalanced across layers, rather than applying these operations to all packet losses universally. This partial application of the remedy (reordering/buffering) optimizes resource usage by avoiding excessive actions on already-balanced loss cases.
3Manufacturing precision
If sequence number gaps are detected and reordering triggered, then packet ordering accuracy is improved, but detection complexity increases due to layered protocol interactions
Solution Approach 1:
The patent merges the detection functions of the PDCP and RLC layers by having the PDCP layer utilize the RLC layer's missing packet detection results. Instead of implementing independent detection at both layers, the system combines their functionalities, where the PDCP layer's sequence number gap detection is informed by the RLC layer's packet loss information, reducing overall detection complexity while maintaining ordering accuracy.
Solution Approach 2:
The patent implements feedback mechanisms where the RLC layer's packet loss detection information is fed back to the PDCP layer to guide its reordering decisions. This feedback loop allows the PDCP layer to adjust its detection and reordering behavior based on the actual state of packet reception at the lower layer, improving accuracy while managing complexity through coordinated information exchange.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A wireless communication device is described. The wireless communication device includes a memory and a processor in electronic communication with the memory. The processor is configured to determine a packet data convergence protocol (PDCP) packet count corresponding to a last radio link control (RLC) packet received in-sequence. The processor is also configured to detect a missing PDCP packet based on a comparison of the PDCP packet count and a sequence number of a last PDCP packet received in-sequence.