Currently,e-learning is one of the most prevalent educational methods because of its need in today’s world.Virtual classrooms and web-based learning are becoming the new method of teaching remotely.The students exper...Currently,e-learning is one of the most prevalent educational methods because of its need in today’s world.Virtual classrooms and web-based learning are becoming the new method of teaching remotely.The students experience a lack of access to resources commonly the educational material.In remote loca-tions,educational institutions face significant challenges in accessing various web-based materials due to bandwidth and network infrastructure limitations.The objective of this study is to demonstrate an optimization and queueing tech-nique for allocating optimal servers and slots for users to access cloud-based e-learning applications.The proposed method provides the optimization and queue-ing algorithm for multi-server and multi-city constraints and considers where to locate the best servers.For optimal server selection,the Rider Optimization Algo-rithm(ROA)is utilized.A performance analysis based on time,memory and delay was carried out for the proposed methodology in comparison with the exist-ing techniques.The proposed Rider Optimization Algorithm is compared to Par-ticle Swarm Optimization(PSO),Genetic Algorithm(GA)and Firefly Algorithm(FFA),the proposed method is more suitable and effective because the other three algorithms drop in local optima and are only suitable for small numbers of user requests.Thus the proposed method outweighs the conventional techniques by its enhanced performance over them.展开更多
The Web cluster has been a popular solution of network server system because of its scalability and cost effective ness. The cache configured in servers can result in increasing significantly performance, In this pape...The Web cluster has been a popular solution of network server system because of its scalability and cost effective ness. The cache configured in servers can result in increasing significantly performance, In this paper, we discuss the suitable configuration strategies for caching dynamic content by our experimental results. Considering the system itself can provide support for caching static Web page, such as computer memory cache and disk＇s own cache, we adopt a special pattern that only caches dynamic Web page in some experiments to enlarge cache space. The paper is introduced three different replacement algorithms in our cache proxy module to test the practical effects of caching dynamic pages under different conditions. The paper is chiefly analyzed the influences of generated time and accessed frequency on caching dynamic Web pages. The paper is also provided the detailed experiment results and main conclusions in the paper.展开更多
提出了一种基于段流行度的移动流媒体代理服务器缓存算法P2CAS2M2(proxy caching algorithm based on segment popularity for mobile streaming media),根据移动流媒体对象段的流行度,实现了代理服务器缓存的接纳和替换,使移动流媒体...提出了一种基于段流行度的移动流媒体代理服务器缓存算法P2CAS2M2(proxy caching algorithm based on segment popularity for mobile streaming media),根据移动流媒体对象段的流行度,实现了代理服务器缓存的接纳和替换,使移动流媒体对象在代理服务器中缓存的数据量和其流行度成正比,并且根据客户平均访问时间动态决定该对象缓存窗口大小。仿真结果表明,对于代理服务器缓存大小的变化,P2CAS2M2比A2LS(adaptive and lazy segmentation algorithm)具有更好的适应性,在缓存空间相同的情况下,能够得到更大的被缓存流媒体对象的平均数,更小的被延迟的初始请求率,降低了启动延时,而字节命中率接近甚至超过A2LS。展开更多
介绍了提高Web服务器性能的前沿技术——分布式Web服务器系统,讨论了现有各种方案的优缺点,在此基础上提出一种新的分布式Web服务器系统.该系统使用基于标记的缓存协作用户请求分发方法(tag based cache cooperative Web requests distr...介绍了提高Web服务器性能的前沿技术——分布式Web服务器系统,讨论了现有各种方案的优缺点,在此基础上提出一种新的分布式Web服务器系统.该系统使用基于标记的缓存协作用户请求分发方法(tag based cache cooperative Web requests distribution,简称TB-CCRD),通过前端机把系统中各个Web服务器的缓存组织成一个大的虚拟缓存系统,提高系统的整体缓存命中率,缩短了请求的响应时间;通过分布式处理TCP连接转交来消除前端机的性能瓶颈;利用标记通告URL在缓存中的位置,避免了额外的系统内部通信.从而得到了一个可扩展的高性能分布式Web服务器系统.展开更多
文摘Currently,e-learning is one of the most prevalent educational methods because of its need in today’s world.Virtual classrooms and web-based learning are becoming the new method of teaching remotely.The students experience a lack of access to resources commonly the educational material.In remote loca-tions,educational institutions face significant challenges in accessing various web-based materials due to bandwidth and network infrastructure limitations.The objective of this study is to demonstrate an optimization and queueing tech-nique for allocating optimal servers and slots for users to access cloud-based e-learning applications.The proposed method provides the optimization and queue-ing algorithm for multi-server and multi-city constraints and considers where to locate the best servers.For optimal server selection,the Rider Optimization Algo-rithm(ROA)is utilized.A performance analysis based on time,memory and delay was carried out for the proposed methodology in comparison with the exist-ing techniques.The proposed Rider Optimization Algorithm is compared to Par-ticle Swarm Optimization(PSO),Genetic Algorithm(GA)and Firefly Algorithm(FFA),the proposed method is more suitable and effective because the other three algorithms drop in local optima and are only suitable for small numbers of user requests.Thus the proposed method outweighs the conventional techniques by its enhanced performance over them.
基金Supported by the National Natural Science Foun-dation of China (90204008)
文摘The Web cluster has been a popular solution of network server system because of its scalability and cost effective ness. The cache configured in servers can result in increasing significantly performance, In this paper, we discuss the suitable configuration strategies for caching dynamic content by our experimental results. Considering the system itself can provide support for caching static Web page, such as computer memory cache and disk＇s own cache, we adopt a special pattern that only caches dynamic Web page in some experiments to enlarge cache space. The paper is introduced three different replacement algorithms in our cache proxy module to test the practical effects of caching dynamic pages under different conditions. The paper is chiefly analyzed the influences of generated time and accessed frequency on caching dynamic Web pages. The paper is also provided the detailed experiment results and main conclusions in the paper.
文摘提出了一种基于段流行度的移动流媒体代理服务器缓存算法P2CAS2M2(proxy caching algorithm based on segment popularity for mobile streaming media),根据移动流媒体对象段的流行度,实现了代理服务器缓存的接纳和替换,使移动流媒体对象在代理服务器中缓存的数据量和其流行度成正比,并且根据客户平均访问时间动态决定该对象缓存窗口大小。仿真结果表明,对于代理服务器缓存大小的变化,P2CAS2M2比A2LS(adaptive and lazy segmentation algorithm)具有更好的适应性,在缓存空间相同的情况下,能够得到更大的被缓存流媒体对象的平均数,更小的被延迟的初始请求率,降低了启动延时,而字节命中率接近甚至超过A2LS。
文摘介绍了提高Web服务器性能的前沿技术——分布式Web服务器系统,讨论了现有各种方案的优缺点,在此基础上提出一种新的分布式Web服务器系统.该系统使用基于标记的缓存协作用户请求分发方法(tag based cache cooperative Web requests distribution,简称TB-CCRD),通过前端机把系统中各个Web服务器的缓存组织成一个大的虚拟缓存系统,提高系统的整体缓存命中率,缩短了请求的响应时间;通过分布式处理TCP连接转交来消除前端机的性能瓶颈;利用标记通告URL在缓存中的位置,避免了额外的系统内部通信.从而得到了一个可扩展的高性能分布式Web服务器系统.
