A comparison between public-domain search engines

The enormous amount of information available today on the Internet requires the use of search tools such as search engines, meta-search engines and directories for rapid retrieval of useful and appropriate information. Indexing a website's content by search engine allows its information to be located quickly and improves the site's usability. In the case of a large number of pages distributed over different systems (e.g. an organization with several autonomous branches/departments) a local search engine rapidly provides a comprehensive overview of all information and services offered. Local indexing generally has fewer requirements than global indexing (i.e. resources, performance, code optimization), thus public-domain SW can be used effectively. In this paper, we compare four open-source search engines available in the Unix environment in order to evaluate their features and effectiveness, and to understand any problems that may arise in an operative environment. Specifically, the comparison includes: o The SW features (installation, configuration options, scalability); o User interfaces; o The overall performance when indexing a sample page set; o Effectiveness of searches; o State of development and maintenance; o Documentation and support.