3,565 research outputs found

    Designing of vague logic based multilevel feedback queue scheduler

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    AbstractMultilevel feedback queue scheduler suffers from major issues of scheduling such as starvation for long tasks, fixed number of queues, and static length of time quantum in each queue. These factors directly affect the performance of the scheduler. At many times impreciseness exists in attributes of tasks which make the performance even worse. In this paper, our intent is to improve the performance by providing a solution to these issues. We design a multilevel feedback queue scheduler using a vague set which we call as VMLFQ scheduler. VMLFQ scheduler intelligently handles the impreciseness and defines the optimum number of queues as well as the optimal size of time quantum for each queue. It also resolves the problem of starvation. This paper simulates and analyzes the performance of VMLFQ scheduler with the other multilevel feedback queue techniques using MatLab

    A FUZZY LOGIC CLASSIFICATION OF INCOMING PACKET FOR VOIP

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    The Voice over Internet Protocol (VoIP) technology is cheaper and does not need new infrastructure because it has availables in the global computer (IP) network. Unfortunately, transition from PSTN to VoIP networks have emerged new problems in voice quality. Furthermore, the transmission of voice over IP networks can generate network congestion due to weak supervision of the traffic incoming packet, queuing and scheduling. This congestion affects the Quality of Service (QoS) such as delay, packet drop and packet loss. Packet delay effects will affect the other QoS such as: unstable voice packet delivery, packet jitter, packet loss and echo. Priority Queuing (PQ) algorithm is a popular technique used in the VoIP network to reduce delays. But, the method can result in repetition. This recursive leads to the next queue starved. To solving problems, there are three phases namely queuing, classifying and scheduling. It will be applied to the fuzzy inference system to classify the queuing incoming packet (voice, video and text). To justify the research of the improved PQ algorithm be compared against the algorithm existing

    Agent Approach QoS Routing in Manet Based on Fuzzy Priority Scheduler

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    As mobile computing gains popularity, the need for Ad-hoc network will continue to grow. The mobile Ad-hoc network is an autonomous system of mobile wireless nodes connected dynamically without any preexisting infrastructure. Here, the nodes are mobile, hence the network topology changes rapidly and unpredictable over time.Here we proposed the mesh based On Demand multicast Routing protocol (OMDRP), in OMDRP the mesh created by using route request and route reply packets. After the mesh we create the cluster, Clustering is a method which aggregates nodes into groups. These groups are contained within the network and they are known as clusters. In mesh we find the multipaths from source to destinations. In that multipaths again we choose one QoS path depending on minimum delay required to reach the destination. In this paper we use the fuzzy scheduling algorithm to schedule the data packets based on their respective priority index,which will improve the network performance. The presented fuzzy scheduler for mobile Ad-hoc networks,determine the priority of the packets. The proposed fuzzy logic scheduling method is simulated by using Cprogramming language. The propsed scheme is better the without fuzzy priority scheduling system

    Fuzzy Logic Control of Adaptive ARQ for Video Distribution over a Bluetooth Wireless Link

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    Bluetooth's default automatic repeat request (ARQ) scheme is not suited to video distribution resulting in missed display and decoded deadlines. Adaptive ARQ with active discard of expired packets from the send buffer is an alternative approach. However, even with the addition of cross-layer adaptation to picture-type packet importance, ARQ is not ideal in conditions of a deteriorating RF channel. The paper presents fuzzy logic control of ARQ, based on send buffer fullness and the head-of-line packet's deadline. The advantage of the fuzzy logic approach, which also scales its output according to picture type importance, is that the impact of delay can be directly introduced to the model, causing retransmissions to be reduced compared to all other schemes. The scheme considers both the delay constraints of the video stream and at the same time avoids send buffer overflow. Tests explore a variety of Bluetooth send buffer sizes and channel conditions. For adverse channel conditions and buffer size, the tests show an improvement of at least 4 dB in video quality compared to nonfuzzy schemes. The scheme can be applied to any codec with I-, P-, and (possibly) B-slices by inspection of packet headers without the need for encoder intervention.</jats:p
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