There are two types of platforms that predominate the server computing environment. The first includes the many flavours of UNIX and the second, Microsoft Windows NT. There are several prominent vendors that have trademarked versions of the UNIX OS.
| Vendor | Tradename(s) |
|---|---|
| Sun Microsystems | SunOS, Solaris |
| Hewlett Packard | HP/UX |
| IBM | AIX |
| Digital (now Compaq) | Digital UNIX |
There are some important freeware version of UNIX available on the Internet. Foremost amongst these is Linux which is a UNIX clone and is widely used because of its excellent features. The significance of UNIX is that it helped build the Internet and a ll flavours of the platform have the TCP/IP bundled into them. Many early web servers were written to run under UNIX: NCSA HTTPd is under copyright at University of Illinois and the CERN HTTPd is under MIT copyright. An increasingly popular freeware serve r called Apache derives from the National Center for Supercomputing Applications (NCSA) and is an option to those who seek an inexpensive implementation of an Intranet (Evans, 19 96, 8). Unfortunately, as with most UNIX flavours, there is considerable knowledge required in establishing a Web server with the Apache platform.
The major platform alternative to UNIX is Windows NT with its own Internet Information Server (IIS). The initial release of IIS was free from the Microsoft website but there was a fee associated with the maintenance support that Microsoft provided (Ben nett, 1996). IIS was designed to run under Windows NT specifically and it was bundled with many of the tools needed to facilitate high functioning Intranets. Most other web servers require the developer to assemble a toolkit, learn multiple languages, and integrate them all to the user's needs. There are some things to consider when choosing either platform. How best will the server platform match the technical staff's expertise (Wagner & Engleman, 1997)?
As an IT decision maker assessing platforms, your chief concern is whether NT-based web server will meet your needs. The answer is that technically, they are at least equal of UNIX HTTPd, although NT employs different methods to achieve the sa me ends. On the other hand, deciding whether the Microsoft way is a good fit for your organization is left as an exercise for the reader. (Bennett, 1996, 107)
If you know that your Intranet server will be used sparingly you could implement a web server at the same expense and ease at which Boegin reported in the Ann Arbor District Library:
we chose a desktop PC (133mhz Pentium - 32 MB RAM) running Windows 95 -- subsequently upgraded to Windows NT -- and Netscape Corporation's Fastrack server as our platform. Microsoft Access was chosen as our database back end due to its availab ility and ease of use. We chose Cold Fusion, an application by Allaire Corporation, to act as an intermediary between our HTML forms and our databases. The total cost of hardware and so ftware for this system was around $2000 (Boegin, 1997, 25)The cost consideration is always a concern for librarians and those who work in library systems, and this example illustrates the economy of such an endeavour. Many examples of web ser ver software are also inexpensive or in some cases free but again, the onus is on the developer to know the various scripting languages [Common Gateway Interface, (CGI), Practical Extraction and Reporting Language (PERL), and Compiled Procedural Language( 'C')(Bannan, 1997)] in order to install them. Some freeware examples include Wide Area Information Service (WAIS) and Simple Web Indexing Systems for Humans (SWISH) and most often the programming languages that are required are dependent on what kind of p latform you are using for your web server (Zorn, 1997). Most were developed for the UNIX environment that may or may not be transferable to other platforms.
Security is another issue when selecting your web server platform but this will be examined later. It is certainly a consideration if you are operating an Intranet that has access to the library's integrated library system. Platform selection also bear s scrutiny for subsequent search engine software selection. Zorn (1997, 33-34) reviewed eight search engines for Intranet use and some were only UNIX or Windows NT supported. Many however support multiple platforms and in some cases, such as OpenText's Li veLink Search support five (Windows NT, UNIX, IBM AIX, SGI, and DEC OSFI). The growth of the industry right now suggests that greater cross platform capabilities will become the norm as sales are predicted to increase. "Zona Reset Inc. predicts intranet s oftware sales will exceed $4 billion in 1997, up 476 million in 1995. In 1998 Zona predicts the figure will be $8 billion, four times the size of the Internet server business" (Jessop, 1997, 58).
What should one look for in a server for your Intranet?
The capacity and the performance of your web server will be affected by the number and types of applications being run, the number of users, and the NOS. The degree to which it can meet your requirements will be determined by its architecture (processor, database, and controller), its scalability, and the degree of fault tolerance and redundancy it provides. (Wesley & Wesley, 1996, 92-93)Scalability refers to the ability of the server to increase capacity through the adding of more memory, another processor, or more hard drive storage. Fault tolerance is the equipment's ability to sustain damage and continue to operate. Fault tolerance is also dependent on the CPU, the memory and the hard drive. Redundancy refers to standby ca pability and is provided by machines or devices that can be quickly replaced. Furthermore, the minimum requirements for a web server would include a 133 MHz CPU, 64 MB of RAM, a Peripheral Component Interconnect (PCI) local bus and Small Computer Systems Interface (SCSI) controller and hard drive.
| Architecture? / CPU? / Memory? / Hard drive? |
|---|
| Operating system (OS) |
| Network operating system (NOS) |
| Number of nodes |
| Concurrent applications |
| Types of applications |
| Processing peaks |
| Fault tolerance and redundancy |
| Scalability requirements |
| Distributed applications |
(Wesley & Wesley, 1996, 98)
Part 1: Intranets
Philosophy