Enhancing Error Recovery in IEEE 802.11 with PIFS-Based Solution
This document discusses error recovery in synchronous multiple frame transmission according to IEEE 802.11 standards. It covers the process of identifying transmission failures, waiting for responses, and implementing PIFS-based recovery mechanisms. The proposed solution suggests synchronizing AckTimeout values across STAs within specific boundaries to improve recovery efficiency.
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author. Download presentation by click this link. If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
E N D
Presentation Transcript
September 2020 doc.: IEEE 802.11-20/1278r0 Error Recovery in Synchronous Multiple Frame Transmission Date: 2020-10-20 Authors: Name Affiliations Address Phone email 2840 Junction Ave, San Jose, CA 95134 yongho.seok@mediatek. com Yongho Seok MediaTek Inc. Kaiying Lu MediaTek Inc. James Yee MediaTek Inc. Submission Slide 1 Yongho Seok (MediaTek)
September 2020 doc.: IEEE 802.11-20/1278r0 Recap: Transmission Failure of an MPDU In 802.11mc Draft 3.0, a transmission failure of an MPDU is defined as follows: After transmitting an MPDU that requires an immediate response: The STA shall wait for a timeout interval of duration aSIFSTime + aSlotTime + aRxPHYStartDelay, starting when the MAC receives a PHY-TXEND.confirm primitive. If a PHY-RXSTART.indication primitive does not occur during the timeout interval, the transmission of the MPDU has failed. If a PHY-RXSTART.indication primitive does occur during the timeout interval, the STA shall wait for the corresponding PHY- RXEND.indication primitive to recognize a valid response MPDU that either does not have a TA field or is sent by the recipient of the MPDU requiring a response. If anything else, including any other valid frame, is recognized, the transmission of the MPDU has failed. Submission Slide 2 Yongho Seok (MediaTek)
September 2020 PIFS based Recovery after Transmission Failure (AckTimeout) doc.: IEEE 802.11-20/1278r0 When a MLD that is a TXOP holder does not receive any PHY-RXSTART.indication primitive from all STAs during the AckTimeout interval, the MLD may perform the PIFS recovery procedure. The AckTimeout is aSIFSTime + aSlotTime + aRxPHYStartDelay. It starts at the PHY-TXEND.confirm primitive of the soliciting PPDU. Submission Slide 3 Yongho Seok (MediaTek)
September 2020 PIFS based Recovery after Transmission Failure (AckTimeout) doc.: IEEE 802.11-20/1278r0 However, if a MLD is a non-STR MLD, When a transmission failure is recognized at the different timing based on AckTimeout, the CS mechanism (see 10.3.2.1 (CS mechanism)) indicates that the medium may be busy at the TxPIFS slot boundary because of the IDC Interference caused by another STA in the same MLD. Error can t be recovered. Submission Slide 4 Yongho Seok (MediaTek)
September 2020 PIFS based Recovery after Transmission Failure (AckTimeout) doc.: IEEE 802.11-20/1278r0 The proposed solution is that the AckTimeout values of STAs in the MLD are synchronized within 4 s (aRxTxTurnaroundTime) boundary. The AckTimeout value of a STA is set to a value from aSIFSTime + aSlotTime + aRxPHYStartDelay to aSIFSTime + aSlotTime + aRxPHYStartDelay + 4 s. 4 s is derived from 8 s aRxTxTurnaroundTime, where 8 s is the maximum value of the ending times difference between the soliciting PPDUs. Submission Slide 5 Yongho Seok (MediaTek)
September 2020 PIFS based Recovery after Transmission Failure (Invalid Response) doc.: IEEE 802.11-20/1278r0 When a MLD that is a TXOP holder successes on a transmission in a link but it received an invalid response in other link, the STA may perform the following PIFS recovery procedure. Submission Slide 6 Yongho Seok (MediaTek)
September 2020 PIFS based Recovery after Transmission Failure (Invalid Response) doc.: IEEE 802.11-20/1278r0 However, if a MLD is a non-STR MLD, When a transmission failure is recognized from the lastly arrived BA frame, the CS mechanism (see 10.3.2.1 (CS mechanism)) indicates that the medium may be busy at the TxPIFS slot boundary because of the IDC Interference caused by another STA in the same MLD. Error can t be recovered. Submission Slide 7 Yongho Seok (MediaTek)
September 2020 PIFS based Recovery after Transmission Failure (Invalid Response) doc.: IEEE 802.11-20/1278r0 The proposed solution is that the PIFS recovery procedures of STAs in the MLD are simultaneously ended within 4 s (aRxTxTurnaroundTime) boundary. An inter-frame space (e.g., STA1) is set to a value from a SIFS to the PIFS + 4 s. 4 s is derived from 8 s aRxTxTurnaroundTime, where 8 s is the maximum value of the ending times difference between the BA frames. Submission Slide 8 Yongho Seok (MediaTek)
September 2020 doc.: IEEE 802.11-20/1278r0 Conclusion In a synchronous multiple frame transmission, an error recovery procedure should consider an IDC interference if a non-STR MLD is a TXOP holder. And, both the backoff based recovery and the PIFS based recovery should support a synchronization mechanism of a start time of the PPDUs on multiple links. Submission Slide 9 Yongho Seok (MediaTek)
September 2020 doc.: IEEE 802.11-20/1278r0 Straw Poll 1 Do you support that the AckTimeout values of STAs in the MLD are synchronized within 4 s (aRxTxTurnaroundTime) boundary? NOTE- The AckTimeout value of STAs in the MLD is set to a value from aSIFSTime + aSlotTime + aRxPHYStartDelay to aSIFSTime + aSlotTime + aRxPHYStartDelay + 4 s. Submission Slide 10 Yongho Seok, MediaTek
September 2020 doc.: IEEE 802.11-20/1278r0 Straw Poll 2 Do you support that the PIFS recovery procedures of STAs in the MLD are simultaneously ended within 4 s (aRxTxTurnaroundTime) boundary? NOTE- An inter-frame space of STAs in the MLD is set to a value from a SIFS to the PIFS + 4 s. Submission Slide 11 Yongho Seok, MediaTek
