Title
EARC: Enhanced Adaptation of Link Rate and Contention Window for IEEE 802.11 Multi-Rate Wireless Networks
Abstract
IEEE 802.11 wireless network supports multiple link rates at the physical layer. Each link rate is associated with a certain required Signal-to-Interference-and-Noise Ratio (SINR) threshold for successfully decoding received packets. On transmission failures, the 802.11 DCF performs a binary exponential backoff mechanism to discourage channel access attempts, hoping to reduce congestion. When traditional link adaptation is applied, both rate reduction and binary backoff represent double penalties for this wireless link, which may cause overly conservative transmission attempts. On the other hand, once transmission succeeds, 802.11 DCF resets the backoff contention window to the minimum value to encourage channel access attempts. At the same time, traditional link adaptation may also decide to increase the data rate, which leads to overly aggressive transmission attempts. We observe this improper interaction of link rate and backoff mechanism that harms the 802.11 system performance, due to separate consideration of those two parameters. In this paper, we propose to jointly adapt the rate and backoff parameters. Specifically, an Enhanced Adaptation of link Rate and Contention window, abbreviated as EARC, is devised. EARC is a closed-loop (receiver-assisted) link rate adaptation protocol that jointly considers the backoff mechanism. With only one extra byte carried by the DATA packet, EARC incurs little controlling overhead despite its receiver-assisted nature. Moreover, since SINR information commonly utilized by receiver-assisted protocols is not precisely supported in real devices, we introduce a rate selection reference (RSR) table empirically derived by constantly monitoring the environmental energy level and reception behavior. The RSR table then guides the receiver to select the best sustainable rate for the transmitter. Simulation results demonstrate the RSR table is a practical option for making the rate decision, and the proposed EARC approach is effective - n maintaining high system throughput, compared to other link adaptation algorithms.
Year
DOI
Venue
2012
10.1109/TCOMM.2012.071312.110145
IEEE Transactions on Communications
Keywords
Field
DocType
contention resolution,radio links,protocols,multiple link rates,ieee 802.11 dcf,ieee 802.11 multirate wireless networks,closed-loop receiver-assisted link rate adaptation protocol,rate selection reference table,radiofrequency interference,transmission failures,transmitter,ieee 802.11,sinr information,backoff contention window,rsr table,binary exponential backoff mechanism,telecommunication network reliability,wireless link,rate reduction,enhanced adaptation of link rate and contention window,data packet,physical layer,arf,sinr threshold,radio networks,link adaptation,signal-to-interference-and-noise ratio,beb,environmental energy level monitoring,multi-rate,earc,ieee 802 11,interference,signal to noise ratio,energy states,wireless communication
Link adaptation,Exponential backoff,Wireless network,IEEE 802.11,Computer science,Network packet,Computer network,Communication channel,Physical layer,Throughput
Journal
Volume
Issue
ISSN
60
9
0090-6778
Citations 
PageRank 
References 
5
0.44
18
Authors
3
Name
Order
Citations
PageRank
Tingyu Lin122321.88
Ching-Yi Tsai291.18
Kun-Ru Wu3348.37