Overheads in Data Stream Over WLAN July 2001 doc.: IEEE 802.11-01/434r1 July 2002 Overheads in Data Stream Over WLAN Tan Pek Yew, Jun Hirano & Takashi Aramaki (Panasonic) Tan Pek-Yew, Panasonic Wei Lih Lim, Matsushita Electric Ind.

Content Definition of Data Stream in .11 WLAN July 2002 Content Definition of Data Stream in .11 WLAN Burst Ack Transmission in TXOP in .11e Header Information Bit Rates in TXOP Numerical Results Conclusions Tan Pek-Yew, Panasonic

Traffic Stream - Definition July 2002 Traffic Stream - Definition Based on IEEE802.11e Draft 3.0 A traffic stream is a set of MSDUs to be delivered subject to the QoS parameter values provided to the MAC in a particular traffic specification (TSPEC) Tan Pek-Yew, Panasonic

Burst Transmission in TXOP (not Fragmented) July 2002 Burst Transmission in TXOP (not Fragmented) TXOP = 3968 uS Burst Data = 10 packets Total Data TX Time = 3868usec CF POLL(44uS) Burst Data(368uS) Burst Data BurstAckReq(24uS) Burst Data Burst Data BurstAck(44uS) CF POLL SIF(16uS) SIF SIF SIF SIF SIF SIF Based on 54 Mbps PHY Full Header with Payload (2312 bytes) = 368 usec Data Packet Header size = 4 usec % for Address Fields = 4*(10)/3868 = 1.03% Tan Pek-Yew, Panasonic

Burst Transmission in TXOP (Fragmented) July 2002 Burst Transmission in TXOP (Fragmented) TXOP = 3712 uS Burst Data = 5 packets Total Data TX Time = 3612 uS CF POLL(44uS) Burst Data(704uS) Burst Data Burst Data Burst Data BurstAckReq(24uS) BurstAck(44uS) CF POLL SIF(16uS) SIF SIF SIF SIF SIF SIF Fragment to 9 MPDUs Payload(1) (256 bytes) H Payload(9) (264 bytes) H SIF Based on 54 Mbps PHY Full Header with Payload (256-264 bytes) = 64 usec Header size overhead = 4 usec % for Address Fields = 4*(5*9)/3612 = 4.98% Tan Pek-Yew, Panasonic

Header Address Bit Rates July 2002 Numerical Results Assumptions Same PHY overheads as data rates increases Worst Case Scenarios Encountered – Fragmented Packets PHY (Mpbs) Header Address Bit Rates 54 2.69 Mbps 108 5.38 Mbps 216 10.76 Mbps 432 21.52 Mbps Tan Pek-Yew, Panasonic

Conclusions To Achieve High Throughput July 2002 Conclusions To Achieve High Throughput Reduction of irrelevant header information Substantial data rates can be saved from header information Proposed that High Throughput and Future version of WNG to look into irrelevant information be removed for data packets from one traffic stream Tan Pek-Yew, Panasonic