RTS/CTS Framework Paradigm and WLAN Qos Provisioning Methods

Abstract

Abstract-Wirelesslocal area network (WLAN) communications performance design and management have evolved a lot to be where they are today. They went through some technology's amendments and innovations. But, some performance tools remained almost unchanged and play a fundamental role in contemporary networking solutions despite the latest innovations higher influence on their indisputable and important function. That is the case with Request to send (RTS) and consent to receive (CTS) protocols. They are among the former technologies, which helped for transmission control with better performance in WLAN environment. They are so important, particularly since the advent of sensitive data networking (e.g. internet telephony, audio and video materials distribution) over the internet protocol (IP). Up to recent years following today's multimedia WLAN based networks deployment trends, RTS/CTS) contributed to provide networks with some expected good performance levels prior to the discovery of more sophisticated methods for this purpose (i.e. performance enhancements). And yet, one may question whether the new technologies have rendered RTS/CTS frameworks obsolete; or are they now used only for some specific network applications traffic management? This articles review attempts to comprehensibly study some of the research works, which have had interest in RTS/CTS mechanism as tools for WLAN applications performance support. Various researches have studied these tools from their early innovation as network node's built-in component, through different frameworks associated with WLAN legacy (IEEE 802.11) MAC protocols. This paper analyzed RTS/CTS initial implementation as mere network performance solution from packets' collision avoidance perspective; and then for transmission delay due to hidden nodes and their false deployment. The article closes up on a critical analysis on the possible long time contribution of these protocols into integrated schemes based WLAN QoS performance design.

Development of a method for assessing the effective information transfer rate based on an empirical model of statistical relationship between basic parameters of the Standard 802.11 wireless channel

“…The obtained model (13) uses the measuring parameter P m which can be obtained using software and hardware of Standard 802.11 devices. In addition, based on the V eff parameter, information about the capabilities of the channel to transmit different types of traffic can be obtained.…”

“…In the second stage, the effective data rate in the channel is calculated using the model (13). Moreover, the calculation is performed for all standards according to the coefficients given in Table 2 and Table 3.…”

“…The process of transmitting information in a wireless channel in real conditions involves maintaining connection under the action of destabilizing factors such as interferences, delays, and noise in the transmission path, etc. To minimize the impact of such factors in packets and frames, there is a mechanism for entering additional service information, and a retransmission mechanism is used [13].…”

“…The empirical model (13) makes it possible to estimate the effective data rate for any channel of the Standard 802.11 along its entire length using just the basic energy parameter. Because each Standard 802.11 device has built-in means of measuring the received signal strength, such estimation can be performed in real-time and for all standards simultaneously.…”

Kablosuz Yerel Alan Ağlarında Kanal Kullanımının MAC Katmanında Döngü Tablosu ile Artırılması

“…WLAN'larda Dağıtık Koordinasyon Fonksiyonunda (Distributed Coordination Function-DCF) kullanılan CSMA/CA protokolünde QoS'i artırmak için farklı algoritmalar kullanılarak birçok çalışma gerçekleştirilmiştir [1][2][3]. Yapılan bu çalışmalarda alınan ve gönderilen veri trafiği, birim zamanda işlenen paket miktarı ve gecikme süresi gibi çıkış parametreleri optimize edilmiştir [4][5][6]. TABLE TABLE) WLAN'larda gerçekleştirilen önceki çalışmalarda gecikme süresi, birim zamanda işlenen miktarı gibi çıkış parametrelerini opitimize etmek amacıyla OPNET Modeler üzerinden elde edilen veri setleri için farklı algoritmalar kullanılarak giriş değişkenleri optimize edilmiştir.…”