Investigation of QoS in VoIP over WiFi Coexisting with WiMAX Networks

In recent trends video conveying entire wide area network via IP based streaming connectivity. In the past people listened to an audio broadcast through a radio and watched a video program broadcast through a TV. They used the telephone network to interactively communicate with another party. But now they want to use the Internet not only for text and image communications but also for audio and video services. The most important in this service is the transmission of voice or video which is done by Voice over Internet Protocol. Thus the transmission of voice over VoIP is done better by WiMAX. But highly developed areas are using only WiFi. Since WiFi is a wireless technology and have many benefits the number of fixed and mobile users in the particular coverage area also increases. The users in pedestrian environment get a frequent connection to the network than the users in a vehicular environment especially the train. It is due to the lack of coverage distance by the network. So it is very necessary to increase the coverage area for larger distance. The solution to this problem is integrating WiMAX and WiFi.