In today's era of communication where wireless media is replacing wired media, security is of utmost concern. The WiMAX technology was developed after the analysis of security failures in IEEE 802.11 technology. As WiMAX has a very high coverage area, security becomes one of the most important issues. Both mobile and fixed WiMAX has many striking features like connection-oriented MAC layer, pre...

A hotspot offers Internet access over Wi-Fi through the use of a router connected to a link to an internet service provider. If the link is wireless, e.g., WiMAX, the hotspot becomes mobile. Under such a heterogeneous network, it is challenging to provide QoS and/or to control data rate. In this paper, we design and implement a policy server for commercial WiMAX mobile hotspots based on Policy ...

The demand of wireless communication is high data rate along with error free communication. An error in communication can be reduced by employing proper channel coding techniques. In this paper, authors have proposed the hybrid channel coding scheme in which convolution codes and turbo codes are combined to perform together. This scheme helps to provide smooth communication with high data rate ...

Nowadays, wireless packet data services are provided over Wireless MAN (WMAN) at a high data service rate, while 3G cellular networks provide wide-area coverage at a low data service rate. The integration of mobile WiMAX and 3G networks is essential, to serve users requiring both high-speed wireless access as well as wide-area connectivity. In this paper, we propose a cross-layer optimization s...

The convergence of mobile homogeneous networks to heterogeneous networks had put forth the challenge of seamless handovers between different radio access networks with maintained QoS. Efficient vertical handover decision strategy is vital for heterogeneous WiMax/WLAN networks that in return do combine advantages from both access technology in terms of data rates and coverage, offering high QoS ...

Link adaptation is a process of paramount importance to optimize the performance of wireless communication systems. However, standardization committees have not standardized link adaptation procedures in order to foster competitiveness among vendors. As a consequence, many research projects have been conducted on this field and several strategies have been presented and tested, mainly for High ...

The emerging technology, which allows high speed broadband wireless access, is the WiMAX technology which is based on the IEEE 802.16 family of standards. Mobile WiMAX (Worldwide Interoperability Microwave Access) is a wireless system based on the IEEE 802.16e [1] standard. In this paper occurrence of the handover in Wimax & LTE systems is shown and what are the requirements that have to be con...

IEEE 802.16e, mobile Wi-Max, is a wireless technology used to provide very high data rate over large areas to a large number of users where broadband is unavailable. WiMAX network operators provide WiMAX subscriber units that enable connection to the metropolitan WiMAX network while WiFi units are used for connecting local devices within homes or businesses. In this paper, we use OPNET Modeler ...

In this paper a heterogeneous network model based on the IMS-SIP (session Initiation protocol) with the help of Authentication, Authorization, and Accounting (AAA) protocol that integrates the Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS) and Wireless Local Area Network (WLAN) technologies is proposed to improve QoS. The proposed Loos...

The conflict between intellectual property rights and standardization has become clearly visible with the examples of the second generation (2G) wireless GSM system and the third generation’s (3G) WCDMA and CDMA-2000 systems. Now, on the verge of standardizing fourth generation (4G) systems, the mobile telecommunications industry has become highly sensitive to issues resulting from the ownershi...