Paper id 2720145

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International Journal of Research in Advent Technology, Vol.2, No.7, July 2014 E-ISSN: 2321-9637

Vertical Handoff Performance in WLAN Wireless Networks Renu1, Anil Dudy2 Electronics and communication1, 2,Shri Baba Mastnath Engg. college1, 2 Email:renudalal89@gmail.com1, anildudy10@gmail.com2

Abstract- The WiFi handoff setup compares the data traffic received by different APs in the network. Since the initial stations of AP_0 are mobile ones, AP_0 receives data traffic only at the beginning and then at end of simulation when its stations start their tour and come back. Additionally, it receives data traffic when the stations started from south visit its section and get connected to it. In contrast to AP_0, AP_2 has stable stations, so the data traffic received by it does not drop to 0 like AP_0's traffic. As expected, its received data traffic doubles when the moving stations from west and south cross its section. AP_3 is visited by all moving stations at the same time. Hence, its received data traffic is tripled when this happens during simulation. Hence the throughput and delay for the wlan MS is obtained. The vertical handover setup consists of a gateway, application server providing voice service to the wimax BS and to the wlan router. Index Terms- AP, DCF, PCF, LAN, WLAN 1. INTRODUCTION

2. WIRELESS LAN SYSTEM

Communication is always necessary in building relations to mankind, when two persons meet they need some medium to interchange their views but due to distance barriers some tools are required to communicate each other. At the end of 19th century, renowned scientist Graham Bell laid the first stone in the field of communication using different tools regardless of distance. He invented first wired base telephony equipment. It was the solution for the voice communication for the people how far apart they are. After this radio based communication systems Era started. It was an extension of wired based networks.

The Wireless Local Area Network (WLAN) is an unlicensed band of 802.11 ISM frequency band. 802.11 is one of the recent communication technologies of IEEE standard. It specifies medium access control (MAC) and physical layer that is why it is called Wireless LAN. It has three widely used types which operates on different frequency bands. These three types are 802.11a, 802.11b and 802.11g. 802.11a operates on 5 GHz frequency band and it gives the maximum data rate speed of 54 Mbps, which is higher than 802.11b because 802.11b operates on 2.4 GHz frequency band and give the maximum data rate speed of 11Mbps. 802.11b operates. 802.11g is recently developed standards of Wireless LAN. It also operates on 2.4 GHz frequency band and give the maximum data rate speed of 54 Mbps. In 802.11 Wireless LAN standards, the two types of MAC protocols Distributed Coordination Function (DCF) and Point Coordination Function (PCF) are used. Nowadays the most applications available in the markets are uses DCF because it is simple, robust and easy to implement.

In the beginning it was developed for some special purposes like military and police usage. With the passage of time these systems emerged to allow common peoples to communicate with each other, rather than using wired based network. After this the age of faster communication and capabilities of voice get started and evolved into new telecommunication system. The capability to achieve wireless access anywhere, anytime, and anyplace has become common expectation as it provides significant flexibility and freedom in mobility. But to achieve global mobility in heterogeneous networks for any mobile device requires seamless connectivity using vertical handoff. Since none of the existing wireless frameworks provide practical solutions for vertical handoff. End-to-End Vertical Handoff (E2EVH) proposed in this paper offers a new concept to perform vertical handoff between heterogeneous wireless networks. To deliver network services without interruption, E2EVH present a novel design to monitor the network availability, it then picks the best accessible network for application layer [1].

DCF is the basic MAC layer function in Wireless LANs, Which used Carrier Sense Multiple Access technique (CSMA) also with an addition of Collision Avoidance of (CA). It resolves the CA problems of the packets transmitted at the same time. Architecture of Wireless LAN Wireless Local Area Network instigate as an overlay to the Wired Local Area Network. Lightweight and Autonomous are two discrete architectures used in WLAN environment.

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