Performance Assessment and Traffic Differentiation in Wireless Local Area Networks

Performance Assessment and Traffic Differentiation in Wireless Local Area Networks


Wireless local area networks (WLANs) are groups of wireless networking nodes within a particular region, such as an organization or building campus, that are capable of radio communication. Wireless local area network (Wireless LANs) technology are widely install and used in many organizations today. A wireless LAN is a flexible data infrastructure configuration execute as an extension to, or as a substitute for, a wired network. It can access and shared information without looking for a place to plug in, and network administrator. Wireless LANs transmit and receive data over by using of radio frequency (RF) technology over the air, minimizing the need for wired connections. It can set up networks without installing physical cables. Nowadays, it has become more popular, in many institutions and domestic users are used wireless LANs are as a general- purpose connectivity. It has become progressively more popular for their consumption in the organisation, university and public hotspot areas such as airports, malls, and hotels. Due to the lack of restrictions for users by releasing the restraint of physical connections as well as an increase the usages of mobile devices such as handhelds, and laptops computers.

The system resources, which are of concern within mobile wireless environments, include such as bandwidth, memory, processing power, in addition to devices, such for the reason that of handhelds, and laptops computers, which work on battery power. Devices cannot execute system programs with high computational requirements because system programs developed for mobile wireless networks must be resource efficient. Hence, there is an acute need to quantify and analyze the performance.

Performance assessment and traffic differentiation

The wireless network performance assessment can be evaluated either randomly or on fixed schedules. To maintain the wireless network assessments shall be performed by an independent and trusted the third party. This should be part of the periodic risk assessment effort to ensure potential wireless LAN threats and vulnerabilities are mitigated. On the other hand, WLAN capacity has verified more elusive than measurements for wired LANs due to the unique features of the wireless medium. i.e., measurements over a single wireless hop, such as in an 802.11 communications network, be able to vary depending upon the hop distance, cross, and contending traffic, the building structure and even the human motion within a measuring test bed. Network performance is assessed by certain parameters such as bandwidth usage perception, end-to-end delay, packet loss, total system throughput, user level response and so on. These

Parameters facilitate both network administrator and mobile users to quantify QoS provide by the network.

Also, wireless networks are highly vulnerable to many kinds of attacks because of their inherent broadcast nature and shared air medium. Due to the variable radio links, wireless networks provide relatively low bandwidth and higher packet loss, and also processing power is less, fewer memory spaces leading to stringent system requirements on the use of system resources. Low cost, ease of operation and mobility support has resulted in the enormous popularity of IEEE 802.11 WLANs.

Therefore, it is essential to determine the performance impact caused by security services in mobile wireless networks In Recent years, Wireless local area network (WLAN) technologies have emerged as a fast-growing market. Unlike the conventional best effort data applications, multimedia applications require quality of service (QoS) support such as guaranteed bandwidth and bounded delay.

The growing popularity of multimedia applications, people wants audio, video and broadband services like High-definition television (HDTV) through WLANs connections. Hence, to offer quality of service (QoS) support IEEE 802.11 standard group has specified a new IEEE 802.11e standard. IEEE 802.11e supports quality of service (QoS) by providing differentiated classes of service in the medium access control (MAC) layer; it also enhances the physical layer so that it can time sensitive multimedia traffic, in addition to traditional data packets.

The WLANs is also categorized according to the network topology (such as Star, Ring, and Bus). It shall be categorized according to the Medium Access Control (MAC) Protocol used (such as Contention-Based MAC and Contention Free MAC). Network architecture depends on the existence time, as well as the signal travelling path from a starting place to a destination.

Historically, performance estimation was primarily concerned with computer systems.

During the 70's and 80's, computer system performance evaluation emerged as an essential component of Computer Science due to rapid and concurrent advancement in computer hardware and computer operating systems. The resultant increased the difficulty of modern computer systems made understanding and evaluating computer systems more difficult.

The scientific method to the study of systems is called the performance assessment. Performance evaluation techniques has been developed in the direction of precisely calculate the effectiveness by means of which system assets are managed at the same time as striving to provide service to facilitate is fair to all customer classes. Viewed while different from the computer design, the objective of performance estimation is determined the
Efficiency and impartiality of a computer be assumed in the direction of work correctly.

A performance assessment study of WLANs seeks on the way to establish the standards used for network performance indices underneath a specified traffic workload and network configuration. Workload categorization on behalf of computer involves the design as well as alternative of traffic types with the intention of afford the inputs intended for WLANs performance evaluation. Performance assessment of network is measures to all dependent on the subject of some degree on the input workload, the system topology, in addition to the choices during controlled parameters or else network default settings.

Through exist empirical studies; the objective is on the way to evaluate the performance of the WLANs at the same time as it is managing real traffic. One drawback of measuring exist traffic is sure with the intention of this measurement involves ‘typical' traffic intended for this network. The advantage of this kind of study exist with the purpose of the measurement involves a real workload. Another drawback of exist traffic measurement is with the purpose of reproducibility of the same traffic workload is typically not possible. This is difficult as soon as the goal is to estimate the impact of changing system components on the whole performance.

