A VOICE PRIORITY QUEUE (VPQ) SCHEDULER FOR VOIP OVER WLANs

The Voice over Internet Protocol (VoIP) application has observed the fastest
growth in the world of telecommunication. The Wireless Local Area Network
(WLAN) is the most assuring of technologies among the wireless networks, which
has facilitated high-rate voice services at low cost and good flexibility. In a voice
conversation, each client works as a sender and as a receiver depending on the
direction of traffic flow over the network.
A VoIP application requires a higher throughput, less packet loss and a higher
fairness index over the network. The packets of VoIP streaming may experience drops
because of the competition among the different kinds of traffic flow over the network.
A VoIP application is also sensitive to delay and requires the voice packets to arrive
on time from the sender to the receiver side without any delay over WLANs.
The scheduling system model for VoIP traffic is still an unresolved problem. A
new traffic scheduler is necessary to offer higher throughput and a higher fairness
index for a VoIP application. The objectives of this thesis are to propose a new
scheduler and algorithms that support the VoIP application and to evaluate, validate
and verify the newly proposed scheduler and algorithms with the existing scheduling
algorithms over WLANs through simulation and experimental environment.
We proposed a new Voice Priority Queue (VPQ) scheduling system model and
algorithms to solve scheduling issues. VPQ system model is implemented in three
stages. The first stage of the model is to ensure efficiency by producing a higher
throughput and fairness for VoIP packets. The second stage will be designed for
bursty Virtual-VoIP Flow (Virtual-VF) while the third stage is a Switch Movement
(SM) technique. Furthermore, we compared the VPQ scheduler with other well
known schedulers and algorithms. We observed in our simulation and experimental
environment that the VPQ provides better results for the VoIP over WLANs.