Link Layer Window Synchronization via Segment Indicators
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communications systems, the inefficiency in synchronizing link layer windows leads to unnecessary over-the-air signaling, flushing of windows, and retransmission of frames when they become out of sync, hindering efficient communication between transmitters and receivers.
Innovation Solution
The method involves decomposing frames into segments, sending acknowledgement requests integrated with the last segment of each frame, and using a response timer to determine the last transmitted segment of the eldest frame for retransmission with a synchronization indicator, allowing the receiver to adjust its window without full reset, thereby maintaining synchronization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If link layer windows are reset when out of synchronization, then synchronization is restored, but communication efficiency deteriorates due to additional signaling, window flushing, and frame retransmission
Solution Approach 1:
The patent segments frames into multiple segments and transmits them individually. Each segment carries a segment number and sequence number, allowing the receiver to identify and reassemble segments in the correct order. This segmentation enables partial acknowledgments and selective retransmission, avoiding the need to reset the entire link layer window when only certain segments are lost or out of sync.
Solution Approach 2:
The patent implements an acknowledgment mechanism where the receiver sends ACK messages back to the transmitter to confirm successful reception of segments. The ACK messages contain information about the highest in-order segment received, enabling the transmitter to track which segments have been successfully delivered and which need retransmission, thereby maintaining synchronization without full window resets.
2Reliability
If full window reset is performed to restore synchronization, then link layer synchronization is achieved, but data flow continuity is disrupted
Solution Approach 1:
The patent performs preliminary actions by sending segments with embedded sequence numbers and acknowledgment requests before actual data transmission completes. The receiver prepares to reassemble segments in order and sends acknowledgments in advance, allowing the transmitter to proactively maintain synchronization state and prevent disruptions to data flow continuity.
Solution Approach 2:
The patent maintains continuous data flow by enabling selective retransmission of only the specific segments that are out of synchronization rather than resetting the entire window. The acknowledgment mechanism allows the transmitter to continue transmitting new segments while simultaneously retransmitting lost segments, ensuring uninterrupted useful action throughout the communication process.
Data Source
AI summary
A method and system for synchronization of link layer windows in a wireless communications system is disclosed. At a transmitter in the wireless communications system, the transmitter transmits a plurality of frames in a transmitter's link layer window, wherein each frame comprises segments and sends a request for an acknowledgement of the plurality of frames to a receiver. Then the transmitter determines a last transmitted segment of an eldest frame of the plurality of frames in the transmitter's link layer window, if a response to the request is not received within a specified time period and sets a synchronization indicator in the determined last transmitted segment of the eldest frame. Finally, the transmitter transmits the determined last transmitted segment of the eldest frame with the synchronization indicator set to the receiver.