In fields such as science and engineering, virtual environment is commonly used to provide replacements for practical hands-on laboratories. Sometimes, these environments take the form of a remote interface to the phy...In fields such as science and engineering, virtual environment is commonly used to provide replacements for practical hands-on laboratories. Sometimes, these environments take the form of a remote interface to the physical laboratory apparatus and at other times, in the form of a complete software implementation that simulates the laboratory apparatus. In this paper, we report on the use of a semi-immersive 3D mobile Augmented Reality (mAR) interface and limited simulations as a replacement for practical hands-on laboratories in science and engineering. The 3D-mAR based interfaces implementations for three different experiments (from micro-electronics, power and communications engineering) are presented;the discovered limitations are discussed along with the results of an evaluation by science and engineering students from two different institutions and plans for future work.展开更多
Cloud computing paradigm is a service oriented system that delivers services to the customer at low cost. Cloud computing needs to address three main security issues: confidentiality, integrity and availability. In th...Cloud computing paradigm is a service oriented system that delivers services to the customer at low cost. Cloud computing needs to address three main security issues: confidentiality, integrity and availability. In this paper, we propose user identity management protocol for cloud computing customers and cloud service providers. This protocol will authenticate and authorize customers/providers in other to achieve global security networks. The protocol will be developed to achieve the set global security objectives in cloud computing environments. Confidentiality, integrity and availability are the key challenges of web services’ or utility providers. A layered protocol design is proposed for cloud computing systems, the physical, networks and application layer. However, each layer will integrate existing security features such as firewalls, NIDS, NIPS, Anti-DDOS and others to prevent security threats and attacks. System vulnerability is critical to the cloud computing facilities;the proposed protocol will address this as part of measures to secure data at all levels. The protocol will protect customers/cloud service providers’ infrastructure by preventing unauthorized users to gain access to the service/facility.展开更多
The exponential growths of the World Wide Web (WWW) users have made the deployment of proxy servers popular on a network with limited resources. WWW clients perceive better response time, improved performance and spee...The exponential growths of the World Wide Web (WWW) users have made the deployment of proxy servers popular on a network with limited resources. WWW clients perceive better response time, improved performance and speed when response to requested pages are served from the cache of a proxy server, resulting in faster response times after the first document fetch. This work proposes cyclic multicast as a scalable technique for improving proxy server performance for next generation networks. The proposed system uses a cyclic multicast engine for the delivery of popular web pages from the proxy server cache to increasingly large users under limited server capacity and network resources. The cyclic multicast technique would be more efficient for the delivery of highly requested web pages from the cache to large number of receivers. We describe the operation of the cyclic multicast proxy server and characterized the gains in performance.展开更多
The total reliance on internet connectivity and World Wide Web (WWW) based services is forcing many organizations to look for alternative solutions for providing adequate access and response time to the demand of thei...The total reliance on internet connectivity and World Wide Web (WWW) based services is forcing many organizations to look for alternative solutions for providing adequate access and response time to the demand of their ever increasing users. A typical solution is to increase the bandwidth;this can be achieved with additional cost, but this solution does not scale nor decrease users perceived response time. Another concern is the security of their network. An alternative scalable solution is to deploy a proxy server to provide adequate access and improve response time as well as provide some level of security for clients using the network. While some studies have reported performance increase due to the use of proxy servers, one study has reported performance decrease due to proxy server. We then conducted a six-month proxy server experiment. During this period, we collected access logs from three different proxy servers and analyzed these logs with Webalizer a web server log file analysis program. After a few years, in September 2010, we collected log files from another proxy server, analyzed the logs using Webalizer and compared our results. The result of the analysis showed that the hit rate of the proxy servers ranged between 21% - 39% and over 70% of web pages were dynamic. Furthermore clients accessing the internet through a proxy server are more secured. We then conclude that although the nature of the web is changing, the proxy server is still capable of improving performance by decreasing response time perceived by web clients and improved network security.展开更多
The proliferation of web services;and users appeal for high scalability, availability and reliability of web servers to provide rapid response and high throughput for the Clients’ requests occurring at anytime. Distr...The proliferation of web services;and users appeal for high scalability, availability and reliability of web servers to provide rapid response and high throughput for the Clients’ requests occurring at anytime. Distributed Web Servers (DWSs) provide an effective solution for improving the quality of web services. This paper addresses un-regulated jobs/tasks migration among the servers. Considering distributed web services with several servers running, a lot of bandwidth is wasted due to unnecessary job migration. Having considered bandwidth optimization, it is important to develop a policy that will address the bandwidth consumption while loads/tasks are being transferred among the servers. The goal of this work is to regulate this movement to minimize bandwidth consumption. From literatures, little or no attention was given to this problem, making it difficult to implement some of these policies/schemes in bandwidth scarce environment. Our policy “Cooperative Adaptive Symmetrical Initiated Dynamic/Diffusion (CASID)” was developed using Java Development Environment (JADE) a middle ware service oriented environment which is agent-based. The software was used to simulate events (jobs distribution) on the servers. With no job transfer allowed when all servers are busy, any over loaded server process jobs internally to completion. We achieved this by having two different agents;static cognitive agents and dynamic cognitive agents. The results were compared with the existing schemes. CASID policy outperforms PLB scheme in terms of response time and system throughput.展开更多
The lack of current network dynamics studies that evaluate the effects of new application and protocol deployment or long-term studies that observe the effect of incremental changes on the Internet, and the change in ...The lack of current network dynamics studies that evaluate the effects of new application and protocol deployment or long-term studies that observe the effect of incremental changes on the Internet, and the change in the overall stability of the Internet under various conditions and threats has made network monitoring challenging. A good understanding of the nature and type of network traffic is the key to solving congestion problems. In this paper we describe the architecture and implementation of a scalable network traffic moni-toring and analysis system. The gigabit interface on the monitoring system was configured to capture network traffic and the Multi Router Traffic Grapher (MRTG) and Webalizer produces graphical and detailed traffic analysis. This system is in use at the Obafemi Awolowo University, IleIfe, Nigeria;we describe how this system can be replicated in another environment.展开更多
The broadcast nature of wireless network makes traditional link-layer attacks readily available to anyone within the range of the network. User authentication is best safeguard against the risk of unauthorized access ...The broadcast nature of wireless network makes traditional link-layer attacks readily available to anyone within the range of the network. User authentication is best safeguard against the risk of unauthorized access to the wireless networks. The present 802.1× authentication scheme has some flaws, making mutual authentication impossible and open to man-in-the-middle attacks. These characteristics make traditional cryptographic mechanism provide weak security for the wireless environment. We have proposed the use of mobile agents to provide dependable Internet services delivery to users, this will guarantee secure authentication in wireless networks and we examine the feasibility of our solution and propose a model for wireless network security.展开更多
文摘In fields such as science and engineering, virtual environment is commonly used to provide replacements for practical hands-on laboratories. Sometimes, these environments take the form of a remote interface to the physical laboratory apparatus and at other times, in the form of a complete software implementation that simulates the laboratory apparatus. In this paper, we report on the use of a semi-immersive 3D mobile Augmented Reality (mAR) interface and limited simulations as a replacement for practical hands-on laboratories in science and engineering. The 3D-mAR based interfaces implementations for three different experiments (from micro-electronics, power and communications engineering) are presented;the discovered limitations are discussed along with the results of an evaluation by science and engineering students from two different institutions and plans for future work.
文摘Cloud computing paradigm is a service oriented system that delivers services to the customer at low cost. Cloud computing needs to address three main security issues: confidentiality, integrity and availability. In this paper, we propose user identity management protocol for cloud computing customers and cloud service providers. This protocol will authenticate and authorize customers/providers in other to achieve global security networks. The protocol will be developed to achieve the set global security objectives in cloud computing environments. Confidentiality, integrity and availability are the key challenges of web services’ or utility providers. A layered protocol design is proposed for cloud computing systems, the physical, networks and application layer. However, each layer will integrate existing security features such as firewalls, NIDS, NIPS, Anti-DDOS and others to prevent security threats and attacks. System vulnerability is critical to the cloud computing facilities;the proposed protocol will address this as part of measures to secure data at all levels. The protocol will protect customers/cloud service providers’ infrastructure by preventing unauthorized users to gain access to the service/facility.
文摘The exponential growths of the World Wide Web (WWW) users have made the deployment of proxy servers popular on a network with limited resources. WWW clients perceive better response time, improved performance and speed when response to requested pages are served from the cache of a proxy server, resulting in faster response times after the first document fetch. This work proposes cyclic multicast as a scalable technique for improving proxy server performance for next generation networks. The proposed system uses a cyclic multicast engine for the delivery of popular web pages from the proxy server cache to increasingly large users under limited server capacity and network resources. The cyclic multicast technique would be more efficient for the delivery of highly requested web pages from the cache to large number of receivers. We describe the operation of the cyclic multicast proxy server and characterized the gains in performance.
文摘The total reliance on internet connectivity and World Wide Web (WWW) based services is forcing many organizations to look for alternative solutions for providing adequate access and response time to the demand of their ever increasing users. A typical solution is to increase the bandwidth;this can be achieved with additional cost, but this solution does not scale nor decrease users perceived response time. Another concern is the security of their network. An alternative scalable solution is to deploy a proxy server to provide adequate access and improve response time as well as provide some level of security for clients using the network. While some studies have reported performance increase due to the use of proxy servers, one study has reported performance decrease due to proxy server. We then conducted a six-month proxy server experiment. During this period, we collected access logs from three different proxy servers and analyzed these logs with Webalizer a web server log file analysis program. After a few years, in September 2010, we collected log files from another proxy server, analyzed the logs using Webalizer and compared our results. The result of the analysis showed that the hit rate of the proxy servers ranged between 21% - 39% and over 70% of web pages were dynamic. Furthermore clients accessing the internet through a proxy server are more secured. We then conclude that although the nature of the web is changing, the proxy server is still capable of improving performance by decreasing response time perceived by web clients and improved network security.
文摘The proliferation of web services;and users appeal for high scalability, availability and reliability of web servers to provide rapid response and high throughput for the Clients’ requests occurring at anytime. Distributed Web Servers (DWSs) provide an effective solution for improving the quality of web services. This paper addresses un-regulated jobs/tasks migration among the servers. Considering distributed web services with several servers running, a lot of bandwidth is wasted due to unnecessary job migration. Having considered bandwidth optimization, it is important to develop a policy that will address the bandwidth consumption while loads/tasks are being transferred among the servers. The goal of this work is to regulate this movement to minimize bandwidth consumption. From literatures, little or no attention was given to this problem, making it difficult to implement some of these policies/schemes in bandwidth scarce environment. Our policy “Cooperative Adaptive Symmetrical Initiated Dynamic/Diffusion (CASID)” was developed using Java Development Environment (JADE) a middle ware service oriented environment which is agent-based. The software was used to simulate events (jobs distribution) on the servers. With no job transfer allowed when all servers are busy, any over loaded server process jobs internally to completion. We achieved this by having two different agents;static cognitive agents and dynamic cognitive agents. The results were compared with the existing schemes. CASID policy outperforms PLB scheme in terms of response time and system throughput.
文摘The lack of current network dynamics studies that evaluate the effects of new application and protocol deployment or long-term studies that observe the effect of incremental changes on the Internet, and the change in the overall stability of the Internet under various conditions and threats has made network monitoring challenging. A good understanding of the nature and type of network traffic is the key to solving congestion problems. In this paper we describe the architecture and implementation of a scalable network traffic moni-toring and analysis system. The gigabit interface on the monitoring system was configured to capture network traffic and the Multi Router Traffic Grapher (MRTG) and Webalizer produces graphical and detailed traffic analysis. This system is in use at the Obafemi Awolowo University, IleIfe, Nigeria;we describe how this system can be replicated in another environment.
文摘The broadcast nature of wireless network makes traditional link-layer attacks readily available to anyone within the range of the network. User authentication is best safeguard against the risk of unauthorized access to the wireless networks. The present 802.1× authentication scheme has some flaws, making mutual authentication impossible and open to man-in-the-middle attacks. These characteristics make traditional cryptographic mechanism provide weak security for the wireless environment. We have proposed the use of mobile agents to provide dependable Internet services delivery to users, this will guarantee secure authentication in wireless networks and we examine the feasibility of our solution and propose a model for wireless network security.
