Servers

Servers are arranged on the network wherever organisations please. However, links between servers are currently only unidirectional, so one often finds servers referenced by others, but not vice versa. Servers hold the Web pages. They typically store the pages in a filesystem.

Servers are available most systems:

CERN HTTPD.

The W3 daemon program, full featured, with access authorisation, research tools, and so on. This daemon is also used as a basis for many other types of server and gateways. Can also act as a caching proxy server. Authors: Ari Luotonen, Henrik Frystyk, Tim Berners-Lee
Platforms: Unix, VMS.

NCSA HTTPD.

The other very widely used WWW server for Unix systems. It is written in C, and is freely available in the public domain. Many features are similar to CERN's HTTPD. An MS Windows version is also available with most of the features of the Unix version.
Platforms: Unix, MS Windows

GWHIS Server.

Specialised WWW Servers. Commercial, from Quadralay, Inc.
Platforms: Unix

GN.

A single server providing both HTTP and Gopher access to the same data. In C, General Public License. Designed to help the transition of servers from gopher to WWW.
Platforms: Unix.

Plexus.

Tony Sander's server originally based on Marc VanHeyningens Perl Server, but incorporating lots more stuff, including an Archie gateway. It is available in the public domain.
Platforms: Unix.

MacHTTP.

Server for the Apple Macintosh from Chuck Shotton at the University of Texas at Houston. It is shareware, in that you can retrieve a copy to evaluate, but then must pay to register it.
Platforms: Apple Macintosh

SerWeb.

SerWeb is a WWW server that runs under Microsoft Windows 3.1. It's fairly simple, and really needs a dedicated machine to run.
Platforms: MS Windows 3.1, MS Windows NT

WEB4HAM.

Another windows based server.
Platforms: MS Windows

HTTPS for Windows/NT.

Server for Microsoft Windows NT from Chris Adie at the University of Edinburgh. Faster than SerWeb on Windows NT due to being multi-threaded.
Platforms: Windows NT on Intel and Alpha architectures.

OS2HTTPD

An OS/2 server, written by Frankie Fan.
Platforms: OS/2

KA9Q NOS

An internet server package for DOS that includes HTTP and Gopher Servers.
Platforms: DOS

VAX/VMS Server.

Server for systems running DEC VAX/VMS from David Jones at Ohio State University. Uses DECthreads for speed.
Platforms: VMS

REXX for VM.

A server consisting of a small C program which passes control to a server written in REXX. C part by Tim Berners-Lee, REXX part by Bernd Pollermann, both at CERN.
Platforms: VM

HTTP for VM.

By R.M. Troth.
Platforms: VM

Jungle.

Server in Tk/TCL being written by Lindsay Marshall at the University of Newcastle, UK.
Platforms: UNIX

CL-HTTP.

CL-HTTP is a full-featured, object-oriented HTTP server written in Common Lisp by John Mallery at the M.I.T. Artificial Intelligence Laboratory.
Platforms: Symbolics Lisp Machines and ports are underway to Lisps for the MAC and other platforms.

A major concern to commercial sites is security of their information. Apart from conventional network and system security, the WWW servers actually allow you to specify access control to pages of information. Exactly how this is done tends to be server specific. Until the advent of widely available encryption systems, and key distribution systems, we can only trust these systems as far as we can examine them,, and we have no guarantees that information transmitted from a server cannot be eavesdropped.