A Given the importance of finding information on Web servers, there are a large number of search tools available. Understanding their differences and limitations will play a crucial role in your choice.
Web servers, whether they are on the Internet or an internal intranet, do one basic thing. When your browser requests a file, the Web server sends it. Unless all the information that you need to access is unchanging, you will want to be able to run programs on your server -- such as search tools -- that return dynamic information.
To standardise the way Web servers talk to external programs, the Common Gateway Interface (CGI) was developed. The Web server passes information to a CGI program, which then processes it and returns the result, usually as HTML or plain text. This can be displayed by the Web server on the Internet or your intranet.
Often these external programs are referred to as CGI scripts -- programs written in languages such as Perl and Java that require a command interpreter to be installed on the Web server in order to run. The advantage of this is that these programs are portable across platforms. However, Perl scripts often require some modification when ported between the Unix and NT platforms. Perl scripts for Unix often include Unix shell commands, which makes porting them to non-Unix platforms problematic. Java was designed with maximum platform independence in mind. It should be noted that this is different from Java applets that are downloaded to your local computer and are run by your Web browser.
CGI can also be used to make calls to pre-compiled programs, and these run much faster. It can also be used to communicate with database programs such as ORACLE and SQL Server. There are also tools that allow easy publication of documents that are not in HTML format on a Web server. One example is IsysWeb from http://www.isysdev.com. This product is used on the PC World Web site.
So the sort of things that you need to consider are: what platform you are using, whether you plan to move to another platform in the foreseeable future, and the format of the data that you wish to publish on your intranet.
If you just want a search tool that can look at HTML and plain text documents (and you don't want to pay for it!) then EWS from Excite http://www.excite.com/navigate/home.html is worth looking at. This product is available for a wide variety of platforms.
- Roy Chambers