Papers by Keyword: Congestion Control

Abstract: City traffic congestion control as the core problem in ITS, has been paid more and more attention. This article from the actual characteristics of spatial structure of city to divide different traffic levels is based on the flow of people and vehicles that two variables, which foundation underlies a new model of road capacity that describe and analysis the problem of road capacity from the needs of congestion control. Only in this way can we deepen the understanding over the dynamic traffic flow of city, so as to strengthen the purpose of city traffic network congestion and control.

Abstract: The throughput of traditional TCP degrades drastically in high speed satellite links, where the characteristics of long round trip time (RTT) and high bit error rate (BER) happen together. Two typical improved algorithms, Hybla and Westwood, are designed to solve the problems of long RTT and high BER respectively. TCP-HW which combines the advantages of Hybla and Westwood is proposed in this paper, on the basis of consideration of both long RTT and high BER. At slow start and congestion avoidance phase, TCP-HW adopts a radical congestion window (cwnd) growth policy to eliminate the low data transmission rate bring by long RTT as Hybla does. At fast retransmit and fast recover phase, TCP-HW updates the cwnd according to the estimated available bandwidth in Westwood to avoid the frequently unnecessary reduction of cwnd due to high BER. There, the cwnd can be kept large enough to achieve high throughput. Simulation results in NS2 indicate that the change of RTT and packet error rate (PER) has little impact on TCP-HW and the bandwidth utilization of TCP-HW can reach more than fifty percent in the 1Gbps GEO satellite link with 500ms RTT and 0.001 PER. In addition, TCP-HW still have good fairness.

Abstract: This paper presents a fault-tolerant congestion control algorithm for Internet via dynamic output feedback. The controller is designed based on adaptive technique and robust H∞ approach. Simulation result is given to verify the effectiveness of the proposed algorithm.

Abstract: Existing Internet congestion control algorithms did not consider any faults. This paper presents a state feedback fault-tolerant congestion control algorithm which is based on adaptive and robust H_∞ approaches. Simulation result shows that the proposed algorithm has good performance.

Abstract: As the study on and promotion of wireless sensor networks (WSN) are deepening, people have increasingly higher requirements for the transmission speed and transmission performance of wireless sensor networks. Network congestion is an important factor of the transmission performance of a network, so congestion control becomes a hot research topic in the studies on the improvement of WSN services. Based on the study on WSN congestion control mechanism, this paper proposes an adaptive congestion control algorithm and simulates the algorithm. The simulation result shows that this algorithm can ensure stable network performance.

Abstract: With the rapid development of information society, the number of information data transmitting in the Internet is growing quickly, so congestion control becomes very important and it is a hot research field on the Internet now. In this paper, the sliding window, reasons and TCP algorithms of congestion control such as slow start, congestion avoidance, fast retransmit and fast recovery are discussed. Different TCP versions about congestion control are studied and analyzed. As a result, improvements on the congestion control algorithm and the research is still an important topic in the study of Internet congestion control.

Abstract: This paper presents an adaptive congestion control algorithm for Internet with time-varying uncertainties. The controller is designed via dynamic output feedback. Simulation result shows that the proposed algorithm has good performance.

Abstract: Existing Internet congestion control algorithms did not consider time-varying uncertainties. This paper presents a new congestion control algorithm based on adaptive technique and robust H_∞ approach, which can effectively compensate for the time-varying uncertainties. Simulation result shows that the proposed algorithm has good performance.

Abstract: Mobile devices equipped with multiple network interfaces can increase their throughput by making use of parallel transmissions over multiple paths and bandwidth aggregation, enabled by the multipath Transport Control Protocol (MPTCP). However, the existing MPTCP congestion control algorithm adopt a relatively strict definition of the fairness, although to some extent could ensure the fairness of traditional TCP connections, but the total throughput of MPTCP will be limited, which can not make full use of network resources. To solve this problem, this paper propose a congestion control algorithm (FBCC) based on the fairness of bottleneck. The core idea of FBCC is to set up individual fairness factor for each shared bottleneck. NS3 simulation results show that FBCC algorithm not only solves the problem of fairness, but also effectively improve the total throughput of MPTCP connection.

Abstract: An improved congestion control mechanism based on mobile agent for wireless sensor networks is proposed, which includes node-level congestion and link-level congestion control. The formers congestion information is collected and distributed by mobile agents (MA). When mobile agent travels through the networks, it can select a less-loaded neighbor node as its next hop and update the routing table according to the nodes congestion status. Minimum package of node outgoing traffic was preferentially transmitted in the link-level congestion. Simulation result shows that proposed mechanism attains high delivery ratio and throughput with reduced delay when compared with the existing technique.