Search results

Traditionally, file transfer protocol (FTP) servers are major archive providers and users apply the Archie server to locate FTP archives. With the extreme popularity of the WWW, Web servers are now important archive providers and users download archives via HTTP. To reduce HTTP traffic, proxy cache servers are deployed on the Internet. However, we find the hit rate of archives in cache servers is quite low. This study proposes a combination of caching and better searching mechanisms to alleviate the problem. We enable a proxy server to automatically collect WWW and FTP archives from its cache, organize them in the form of an FTP directory, and then offer the directory list to the Archie. Accordingly, users can find archives on WWW and FTP servers through the Archie, and they can directly download archives from the proxy server, thus improving the reuse of cached archives. A system was implemented and operated in a real environment to evaluate the approach and results are discussed.

The World Wide Web (WWW) has become an extremely popular information service. Large HTTP packets result in network congestion. Proxy cache servers are widely deployed on the Internet to overcome this obstacle. However, the approach yields an undesirable phenomenon – a small set of users misuse proxy servers to mirror the entire contents of Web sites. This behavior wastes network resources, increases WWW servers’ loads, increases users’ waiting time, and violates copyrights. Approaches to designing a proxy server with WWW usage control and to making the proxy server effective on local area networks are proposed to prevent such abnormal WWW access and to prioritize WWW usage. Finally, a system, ProxyBreaker, is implemented to demonstrate the approaches. The implementation reveals that the proposed approaches are effective, such that the abnormal Web access does not reoccur.

An archive is a file containing several related files. Many Internet resources, such as freeware, shareware and trail software, are often packaged into archives for easy installation and taking. Additionally, thousands of users search for archives and download them from different sources everyday. In this paper, previous research on archive downloading is extended via proxy cache to support archive searching. Internet proxy cache servers are used to gather a significant number of Web pages, detect those that contain archive links, and then use the obtained data to search archives by description or filename. Two schemes, iterative and backtracking, are proposed to obtain Web pages with archive links. The experimental results indicate that the precision that both of the schemes can achieve is about the same; however, the backtracking scheme reduces the number of checked pages by a factor of 26. Finally, a real system was implemented to demonstrate the proposed approaches.