Download presentation
Presentation is loading. Please wait.
Published bySydnie Northey Modified over 10 years ago
1
January 2002 Khaled Turki et. al, Texas InstrumentsSlide 1 doc.: IEEE 802.11-02/022r0 Submission TID Field Usage in QoS CF-Poll Khaled Turki and Matthew B. Shoemake Texas Instruments Incorporated 12500 TI Blvd. Dallas, Texas 75243 (214) 480-6908 {khaled, shoemake}@ti.com
2
January 2002 Khaled Turki et. al, Texas InstrumentsSlide 2 doc.: IEEE 802.11-02/022r0 Submission Currently The TID field identifies the traffic category or traffic stream to which the MSDU, or fragment thereof, in the frame body field of the present MPDU belongs. The TID may therefore be used at the receiver to sort data and identify traffic streams. What is the current meaning of the TID field in a QoS+CF-Poll? QSTAs responding to a QoS-CF-Poll ignore the TID field of the incoming frame and make a local decision on what frame to respond with. The HC cannot use the TID field to solicit a frame belonging to a certain traffic category or traffic stream from a QSTA
3
January 2002 Khaled Turki et. al, Texas InstrumentsSlide 3 doc.: IEEE 802.11-02/022r0 Submission Bits 0-8Bit 9Bit 10 Bit 11 Bits 12-15Usage TXOP limit, units of 16 microsecondsFECNon- final No Ack TIDQoS data type frames that include CF-Poll sent by the HC reserved (0)FECNon- final No Ack TIDQoS data type frames without CF-Poll sent by the HC TC queue size, units of 128 octetsFECNon- final No Ack TIDQoS data (non-null) frames sent by WSTAs bit 15 =0: TXOP duration requested, units of 16 microseconds bit 15 =1: TC queue size, units of 128 octets rsrv (0) Non- final No Ack TIDQoS null frames sent by WSTAs bit 15 =0: TXOP duration requested, units of 16 microseconds bit 15 =1: TC queue size, units of 128 octets rsrv (0) TIDRR frames Current QoS Control Field
4
January 2002 Khaled Turki et. al, Texas InstrumentsSlide 4 doc.: IEEE 802.11-02/022r0 Submission Potential use of the TID field QoS+CF-Poll (no data): –The TID should indicate the traffic category the HC is soliciting from the recipient of the poll –If the “request TID” or RTID bit is one, it shall indicate that the HC is soliciting a particular traffic category or traffic stream (as specified by the TID), and the polled QSTA shall respond with data of that TID only –When the RTID bit is zero in QoS+CF-Poll, there shall be no restriction on the traffic category of the upstream and a QSTA shall make a local decision –If the RTID bit is set to one and no frames match the TID requested, the station shall respond with a null frame QoS+CF-Poll+Data: –The TID shall indicate the traffic category of the data. No change with respect to current draft! –If the RTID bit is set to zero, the polled QSTA makes a local decision No change with respect to current draft! –If the RTID bit is set to one, it shall indicate that the HC is requesting that the station respond with a frame belonging to the same traffic category as the data it received as indicated by the TID –If the RTID bit is set to one and no frames match the TID requested, the station shall respond with a null frame
5
January 2002 Khaled Turki et. al, Texas InstrumentsSlide 5 doc.: IEEE 802.11-02/022r0 Submission Bits 0-8Bit 9Bit 10 Bit 11 Bits 12-15Usage TXOP limit, units of 16 microsecondsRequ est TID Non- final No Ack TIDQoS data type frames that include CF-Poll sent by the HC reserved (0)rsrvNon- final No Ack TIDQoS data type frames without CF- Poll sent by the HC TC queue size, units of 128 octetsrsrvNon- final No Ack TIDQoS data (non-null) frames sent by WSTAs bit 15 =0: TXOP duration requested, units of 16 microseconds bit 15 =1: TC queue size, units of 128 octets rsrv (0) Non- final No Ack TIDQoS null frames sent by WSTAs bit 15 =0: TXOP duration requested, units of 16 microseconds bit 15 =1: TC queue size, units of 128 octs. rsrv (0) TIDRR frames Proposed Requested TID field RTID bit can replace the FEC bit in data frames of subtype QoS+CF-Poll and the FEC bit can be moved to the Frame Control field
6
January 2002 Khaled Turki et. al, Texas InstrumentsSlide 6 doc.: IEEE 802.11-02/022r0 Submission Benefits Gives the HC the flexibility to control the upstream traffic Enables the implementation of more efficient scheduling algorithms at the HC In situations where a local decision is best, the RTID bit can be set to zero to allow a local decision by the QSTA When the RTID bit is set, complexity is lowered at the QSTA –The QSTA will have reduced frame look up time, as it will know the exact traffic category requested Enables tight control by the HC over critical traffic such as voice. HC can send downstream voice data and simultaneously poll for upstream voice data without the possibility of the QSTA transmitting non-voice data
7
January 2002 Khaled Turki et. al, Texas InstrumentsSlide 7 doc.: IEEE 802.11-02/022r0 Submission Motion Move to direct the editor to modify the draft standard to include an RTID bit in the QoS Control Field with the following functionality: QoS+CF-Poll (no data): –The TID should indicate the traffic category the HC is soliciting from the recipient of the poll –If the “request TID” or RTID bit is one, it shall indicate that the HC is soliciting a particular traffic category or traffic stream (as specified by the TID), and the polled QSTA shall respond with data of that TID only –When the RTID bit is zero in QoS+CF-Poll, there shall be no restriction on the traffic category of the upstream and a QSTA shall make a local decision –If the RTID bit is set to one and no frames match the TID requested, the station shall respond with a null frame QoS+CF-Poll+Data: –The TID shall indicate the traffic category of the data. –If the RTID bit is set to zero, the polled QSTA makes a local decision –If the RTID bit is set to one, it shall indicate that the HC is requesting that the station respond with a frame belonging to the same traffic category as the data it received as indicated by the TID –If the RTID bit is set to one and no frames match the TID requested, the station shall respond with a null frame
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.