Performance analysis of wireless LANs: an integrated packet/flow level approach

Abstract

In this paper we present an integrated packet/flow level modelling approach for analysing flow throughputs and transfer times in 802.11 s. The packet level model captures the statistical characteristics of the transmission of individual packets at the layer, while the flow level model takes into account the system dynamics due to the initiation and completion of data flow transfers. The latter model is a processor sharing type of queueing model reflecting the 802.11 design principle of distributing the transmission capacity fairly among the active flows. The resulting integrated packet/flow level model is analytically tractable and yields a simple approximation for the throughput and flow transfer time. Extensive simulations show that the approximation is very accurate for a wide range of parameter settings. In addition, the simulation study confirms the attractive property following from our approximation that the expected flow transfer delay is insensitive to the flow size distribution (apart from its mean).

Performance Analysis of 802.11 WLANs Under Sporadic Traffic

“…We present an analytical model of the 802.11 DCF that differs from previous work [1][2][3][4][5][6] in addressing all of the following issues: (i) it identifies the critical assumptions in the development of analytical models of 802.11 networks, and presents a fairly simple as well as accurate model of the DCF in presence of non-saturated traffic sources; (ii) it is general enough to account for different arrival processes and traffic patterns, in particular, it applies to the case of bursty traffic like that produced by the TCP protocol; (iii) it evaluates the system performance in a multirate environment; (iv) it applies to the case where a station seizing the channel is entitled to transmit a burst of packets, as specified in the IEEE 802.11e draft standard; (v) it evaluates several metrics of interest, such as the network throughput, the packet loss probability, the distribution of the MAC queue length at the wireless stations, and the average packet delay.…”

Optimal File Splitting for Wireless Networks with Concurrent Access

“…Modeling network performance using processor sharing (PS) based models [2,17,23] is applicable to a variety of communication networks, including CDMA 1xEV-DO, WLAN, and UMTS-HSDPA. In fact, PS models can actually model file transfers over WLANs accurately [11], hence taking into account the complex dynamics of the file transfer application and its underlying protocol-stack, including their interactions.…”

Throughputs in processor sharing models for integrated stream and elastic traffic

“…For instance, the ps service discipline appropriately models the design principle of fair resource sharing by tcp controlled elastic data flows or packet level scheduling schemes in e.g. ip, gprs, umts and wireless local area networks (wlans) [1,2,21,22,24].…”