MIC Length Indication in Fast Basic Service Set Transition Element
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Solution Overview
Problem
In wireless communications, particularly during fast basic service set transitions, the target Fast Basic Service Set Transition (FT) receiver lacks knowledge of the negotiated hash algorithm, making it difficult to determine the message integrity code (MIC) length in the initial messages of the over-the-air FT protocol, which complicates parsing and key management processes.
Innovation Solution
The proposed solution involves using reserved bits in the MIC control field of the Fast Basic Service Set Transition Element (FTE) to indicate the MIC length, allowing the target FT receiver to determine the MIC length directly in the first message, thereby simplifying the parsing process and aligning with the existing standards by not requiring additional elements that would alter the frame order.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the target FT receiver uses the conventional method of determining MIC length from the negotiated hash algorithm, then the parsing process becomes complex and time-consuming, but the reliability of MIC length determination is maintained
Solution Approach 1:
The MIC length is indicated in advance in the FTE message using reserved bits, allowing the target FT receiver to determine the MIC length immediately upon receiving the first message without needing to retrieve PMK-R1 later or perform complex hash algorithm negotiations. This preliminary indication simplifies the parsing process and improves efficiency.
2Ease of operation
If additional elements are added to indicate MIC length, then the MIC length determination becomes straightforward, but the frame order is altered and compatibility with existing standards is compromised
Solution Approach 1:
The reserved bits in the FTE message, which were previously unused, are repurposed to carry MIC length indication. This allows the existing FTE frame structure to serve multiple functions - maintaining backward compatibility with existing standards while enabling new functionality for efficient MIC length determination without altering frame order or requiring additional elements.
3Measurement precision
If the target FT receiver retrieves PMK-R1 at a later time to determine MIC length, then the initial parsing is delayed, but the MIC length determination accuracy is ensured
Solution Approach 1:
The MIC length is embedded in the FTE message itself, allowing the target FT receiver to determine the MIC length immediately during initial message parsing without delaying to retrieve PMK-R1 later. This eliminates the time loss while maintaining accurate MIC length determination through the explicit indication provided in the frame.
Data Source
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AI summary
This disclosure describes systems, methods, and devices related to MIC length indication. A device may utilize one or more reserved bits to indicate a message integrity code (MIC) length. The device may generate a frame comprising the one or more reserved bits, wherein the one or more reserved bits are included in a message integrity code (MIC) control of fast basic service set transition element (FTE). The device may cause to send the frame to one or more STAs.