Distributed Denial of Service (DDoS) attack is one of the biggest threats now days. This paper aims at providing the simulation results of buffer size and attack intensities effect on various queuing algorithms such as DropTail, Fair Queuing (FQ), Stochastic Fair Queuing (SFQ), Deficit Round Robin (DRR) and Random Early Detection (RED) using ns-2 as a simulation environment. The results in this...

The majority of the traffic (bytes) flowing over the Internet today have been attributed to the Transmission Control Protocol (TCP). This strong presence of TCP has recently spurred further investigations into its congestion control mechanism and its effect on the performance of short and long data transfers. In this paper, we investigate the interaction among short and long TCP flows, and how ...

This paper presents a fuzzy based buffer management scheme that performs buffer allocation and packet dropping for wireless multimedia networks in the context of future generation cellular networks. In this scheme, buffers are allocated to requesting application by using buffer allocation factor and packets are dropped for an application by using dropping factor. A buffer allocation factor for ...

In this report we use a previously developed nonlinear dynamic model of TCP to analyze and design Active Queue Management (AQM) Control Systems using RED. First, we linearize the interconnection of TCP and a bottlenecked queue and discuss its feedback properties in terms of network parameters such as link capacity, load and round-trip time. Using this model, we next design an AQM control system...

In this paper, we propose a uni ed mathematical framework based on receding horizon control for analyzing and designing AQM (Active Queue Management) algorithms in stabilizing a given TCP (Transfer Control Protocol) algorithm. The proposed framework is based on a dynamical system of the given TCP and minimization of a linear quadratic cost on the transients in queue length, aggregate rate, jitt...

A great deal of research has been conducted over the last several years into optimizing the performance of Internet communications by way of controlling the size of router queues for packets waiting for transmission over multiplexed links. The optimization algorithm is invariably framed in terms of either minimizing the number of queued packets waiting for transmission, maximizing the outgoing ...

In this paper we investigate the e ectiveness of packet drop mechanisms in conjunction with fair queuing link scheduling and hierarchical link sharing Under fair queuing the link share of a ow changes dynamically due to the arrivals and departures of ows and their bursts This phenomenon becomes more pronounced in the case of hierarchical link sharing Packet drop mechanisms play an integral role...

Using ns-2 simulations, this paper evaluates an Adaptive Explicit Congestion Notification (AECN) router. By receiving round-trip time (RTT) source hints from each TCP flow, AECN divides flows into flow groups based on RTT ranges. AECN uses distinct flow group drop probabilities and a mark front scheme to provide higher goodput and better fairness than Random Early Detection (RED) and Explicit C...

Explicit Congestion Notification (ECN) for IP networks has received considerable attention in recent years, and has been shown to improve TCP goodput. Previous studies have centered on scenarios in which TCP with ECN (TCP/ECN) traffic competes with ECN-unaware traffic. This paper presents case studies in which moderately short flows are all ECN-capable, and compare them with the corresponding c...

The implementation of Active Queue Management (AQM) in Internet routers is a recommendation of the Internet Engineering Task Force. However, none of the current AQM algorithms directly makes use of the correlations present in Internet traffic, which are related to Long Range Dependence (LRD) and Self-Similarity. This is somewhat surprising in that it is well known that LRD is exhibited by Inter...