Scaleable and Smooth TCP-Friendly Receiver-Based Layered Multicast Protocol

In the presence of heterogeneity and scalability, i.e. the case when delivering real-time television content over the Internet, receiver-based layered multicast communication is the most efficient way to deliver real-time video data to a large number of receivers. TCP-friendly Receiver-based Layered Multicast Protocol (TRLMP) is a protocol that supports layered multicast real-time video delivery, while maintaining the fair sharing of the network resources. However, there is room for improvement on the current TRLMPs. Some of the current TRLMPs and their techniques are not efficient in supporting the delivery of real-time video data on the Internet, in particular when the number of receivers is very large. The current TRLMPs' techniques do not allow the receivers to: 1) estimate Round Trip Time (RTT) in a scalable manner; and 2) achieve a steady reception rate because of volatile loss rate estimation. These problems result in stability and scalability problems for TRLMPs. In this thesis, we propose a new TRLMP called Scalable, Smooth and TCP-friendly Receiver-Based Layered Multicast Protocol (SS-TRLMP) to address the problems of the current TRLMP. Similar to other TRLMPs, SS-TRLMP relies on a TCP-equation model to control congestion and fair behaviour of the protocol. However, the equation model requires RTT data, which is problematic to estimate when the number of receivers is too large. In order to address this problem, we proposed the Scalable RTT Estimation Technique (SRTT) for layered multicast communication. The technique models Transmission Control Protocol (TCP) behaviour more accurately than the current RTT estimation techniques. Moreover, the technique is simple and can be easily implemented in the current Internet infrastructure. Stability is one of the requirements of real-time video applications. However, even with the current loss rate smoothing techniques, TRLMPs behaviour is highly volatile. Moreover, in layered multicast communication there is no synchronisation of packets between multicast layers, which causes misinterpretation of loss events at receivers. We address these problems with packet re-ordering at the receiver and the 2-Step Loss Filtering Technique. Packet reordering technique enables the TRLMP to estimate accurate loss rate similar to TCP, and 2STEPS provides better stability and responsiveness than the current techniques. Finally, by combining the techniques of the current TRLMPs and the proposed techniques, we designed SS-TRLMP. The proposed SS-TRLMP has the following properties: TCP fairness, scalability and stability

Enhanced IPFIX flow monitoring for VXLAN based cloud overlay networks

The demands for cloud computing services is rapidly growing due to its fast adoption and the migration of workloads from private data centers to cloud data centers. Many companies, small and large, prefer switching their data to the enterprise cloud environment rather than expanding their own data centers. As a result, the network traffic in cloud data centers is increasing rapidly. However, due to the dynamic resource provisioning and high-speed virtualized cloud networks, the traditional flow-monitoring systems is unable to provide detail visibility and information of traffic traversing the cloud overlay network environment. Hence, it does not fulfill the monitoring requirement of cloud overlay traffic. As the growth of cloud network traffic causes difficulties for the service providers and end-users to manage the traffic efficiently, an enhanced IPFIX flow monitoring mechanism for cloud overlay networks was proposed to address this problem. The monitoring mechanism provided detail visibility and information of overlay network traffic that traversed the cloud environment, which is not available in the current network monitoring systems. The experimental results showed that the proposed monitoring system able to capture overlay network traffic and segregated the tenant traffic based on virtual machines as compare to the standard monitoring system

Expert-seeking activity framework: A proposal

Expert seeking is an activity in which one seeks expertise from someone else in order to solve certain problems. When one realizes he or she requires helps to accomplish tasks that need new skills and knowledge, the process involves many elements including formulating goals and strategies, identifying and selecting expert databases, and expert-seeking systems. By incorporating these elements, we proposed an expert-seeking activity framework, which can be guidance for researchers to better understand the activities of expert seeking

Enhancement of adaptive FEC mechanism for video transmission over 802.11 WLANS

Forward Error Correction (FEC) techniques have been adopted with Automatic Repeat reQuest (ARQ) to overcome packet losses and avoid network congestion in various wireless network conditions. The number of FEC packets need to be generated adaptively because usually wireless network has varying network condition.In the current Adaptive FEC mechanism, the FEC packets are determined based on average queue length and average packet retransmission time. However, in order to determine average queue length, estimating its weight value (i.e. smoothing factor) is a challenging task. Smoothing factor is an important parameter as it affects the generation of FEC packets.Thus, this work conducted the estimation of suitable smoothing factor value to determine the average queue length according to packet loss rate over the wireless network.The simulation results show that the enhanced FEC mechanism outperformed other Adaptive FEC mechanisms in terms of recovery efficiency

Robust multi-dimensional trust computing mechanism for cloud computing

Cloud computing has become the most promising way of purchasing computing resources over the Internet.The main advantage of .cloud computing is its economic advantages over the traditional computing resource provisioning.For cloud computing to become acceptable to wider audience, it is necessary to maintain the quality of service (QoS) commitments specified in the service level agreement.In this paper, the authors propose a robust multi-level trust computing mechanism that can be used to track the performance of cloud systems using multiple QoS attributes.In addition, tests carried out show that the proposed mechanism is more robust than the ones published in the literature

Intelligent DNA signature detection for internet worms

Internet scanning worms are widely regarded to be a major security threat faced by the Internet community today. Active worms spread in an automated fashion flooding the Internet in a very short time.Slammer worm infected more than 90% of vulnerable machines within 10 minutes on January 25th, 2003.Hence it is necessary to monitor and detect the worms as soon as they are introduced to minimize the damage caused by them.This project concentrates on developing an anti-scanning worm detection system that can automatically detect and control the spread of internet scanning worms without any manual intervention.The Intelligent Failure Connection Algorithm (IFCA) developed in this project can detect both stealth and normal worms within a short time.Experiments conducted as part of the evaluation shows that IFCA detects a worm within two scanning cycles of the worm.This is faster than any of the currently available algorithms or mechanisms reported in the literature.The IFCA uses Artificial Immune System (AIS) for the purpose of monitoring and detecting the worms.The Traffic Signature Algorithm (TSA) developed in the project captures the traffic signature of the worm from the infector when it sends the traffic to the victim.The Intelligent DNA Signature Detection Algorithm (IDNASDA) algorithm works by breaking an infection session into different infection phases, each phase containing a number of different traffic such as Internet Control Message Protocol (ICMP), Transmission Control Protocol (TCP), or User Datagram Protocol (UDP).Finally it converts the traffic signature to DNA signature.The tests carried out show that the IDNASD could detect DNA signature for MSBlaster worm

SecNetworkCloudSim: An Extensible Simulation Tool for Secure Distributed Mobile Applications

Fueled by the wide interest for achieving rich-storage services with the lowest possible cost, cloud computing has emerged into a highly desired service paradigm extending well beyond Virtualization technology. The next generation of mobile cloud services is now manipulated more and more sensitive data on VM-based distributed applications. Therefore, the need to secure sensitive data over mobile cloud computing is more evident than ever. However, despite the widespread release of several cloud simulators, controlling user’s access and protecting data exchanges in distributed mobile applications over the cloud is considered a major challenge. This paper introduces a new NetworkCloudSim extension named SecNetworkCloudSim, a secure mobile simulation tool which is deliberately designed to ensure the preservation of confidential access to data hosted on mobile device and distributed cloud’s servers. Through high-level mobile users’ requests, users connect to an underlying proxy which is considered an important layer in this new simulator, where users perform secure authentication access to cloud services, allocate their tasks in secure VM-based policy, manage automatically the data confidentiality among VMs and derive high efficiency and coverage rates. Most importantly, due to the secure nature of proxy, user’s distributed tasks can be executed without alterations on different underlying proxy’s security policies. We implement a scenario of follow-up healthcare distributed application using the new extension

A Review on Cache Replacement Strategies in Named Data Network

Named Data Network (NDN) architecture is one of the newest and future-aspired Internet communication systems. Video-on-Demand (VoD) has rapidly emerged as a popular online service. However, it is costly, considering its high bandwidth and popularity. Internet on-demand video traffic has been growing quite fast, and on-demand video streaming has gained much attention. The problem of this study is that the NDN architecture is processing several forms of online video requests simultaneously. However, limited cache and multiple buffering of requested videos result in loss of data packet as a consequence of the congestion in the cache storage network. Addressing this problem is essential as congestion cause network instability. This work emphasizes on the review of cache replacement strategies to deal with the congestion issue in Named Data Networks (NDN) during the VoD delivery in order to determine the performance (strengths and weaknesses) of the cache replacement strategies. Finally, this study proposes the replacement strategies must be enhanced with a new strategy that depends on popularity and priority regarding the congestion. This study would positively benefits both suppliers and users of Internet videos

Stepping-stone detection technique for recognizing legitimate and attack connections

A stepping-stone connection has always been assumed as an intrusion since the first research on stepping-stone connections twenty years ago. However, not all stepping-stone connections are malicious.This paper proposes an enhanced stepping-stone detection (SSD) technique which is capable to identify legitimate connections from stepping-stone connections.Stepping-stone connections are identified from raw network traffics using timing-based SSD approach.Then, they go through an anomaly detection technique to differentiate between legitimate and attack connections.This technique has a promising solution to accurately detecting intrusions from stepping-stone connections.It will prevent incorrect responses that punish legitimate users