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Choosing a suitable router buffer size is still a significant research problem. The small buffer used guarantees low packet delay but higher chances of packet loss. Similarly, larger buffer results in buffer bloat which causes a high delay in a network. Buffer bloat is a significant problem due to the high changing link characteristics of modern heterogeneous networks. The access links can have connections with speedy links (Gbps) with a small number of packet losses and also have a connection with a susceptible high packet loss with lowbandwidth links like wireless and last-mile connections. Hence, what may be thought to be a rational buffer size, might be flawed when link rates and delays fall below the minimum value. In this paper, extensive NS2 simulations of multi-flow traffic were run to obtain a better-suited buffer size that results in better average throughput and delays over the wired network without extra signaling and computation by the router. The results showed that having a buffer between five and ten packets gave the best average throughput with a low average delay at the congested router.

IEEE known as WiMAX supports wider coverage, higher bandwidth, and quality of service (QoS). 802.16e was introduced which made battery-life of Mobile Station (MS) a critical challenge Since MS are battery powered with an impose rechargeable life. An Efficient Battery Lifetime Aware Power Saving Scheme was proposed to minimize frequent transition of MS to listening-wake mode in order-to reduce power consumption. However, it increases average response delay due to a longer sleep interval used. Thus, an efficient sleep window based power saving scheme (ESPSS) is proposed to reduce the response delay. The ESPSS introduces an average based sleep window to minimize the longer sleep interval. The scheme also proposed a modified minimum and maximum sleep interval to reduce the response delay. The ESPSS was evaluated using a discrete event simulator. The results showed that ESPSS achieves a superior performance compared to the existing Scheme in terms of response delay while improving QoS.

This paper presents a virtualised network environment that serves as a stable and re-usable platform for the analysis of malware propagation. The platform, which has been developed using VMware virtualisation technology, enables the use of either a graphical user interface or scripts to create virtual networks, clone, restart and take snapshots of virtual machines, reset experiments, clean virtual machines and manage the entire infrastructure remotely. The virtualised environment uses open source routing software to support the deployment of intrusion detection systems and other malware attack sensors, and is therefore suitable for evaluating countermeasure systems before deployment on live networks. An empirical analysis of network worm propagation has been conducted using worm outbreak experiments on Class A size networks to demonstrate the capability of the developed platform.

This paper presents a cross-layer countermeasure mechanism to detect and contain self-propagating malware. The mechanism uses a detection technique at the network layer and a data-link containment solution to block traffic from an infected host. The concept has been demonstrated using a software prototype. An empirical analysis of network worm propagation has been conducted to test the capabilities of the developed mechanism. The results show that the developed mechanism is effective in containing self-propagating malware with almost no false positives.