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The Provision of Effective Local, National and International Web Services

Neil Smith

When considering an institutional Web strategy there are three points to be borne in mind.
  1. Demands on the hardware
  2. Using simple, powerful software
  3. Maximising network efficiency

Demands on the Hardware

The exact hardware requirements, and the organisation of that hardware will be based on local considerations. In general, the community feeling is that distributing work across several machines while retaining a central server for general facilities is the right approach. However, this does not always fit in with working practice. A number of guidelines can be laid down.

In general the process of serving documents on the web does not require a large CPU resource, unless the server in question is very popular. Exact figures cannot be provided as there are too many variables in each individual system.

Whilst CPU requirements are, in general low, network bandwidth requirements are nearly always high. The only way to avoid this is to have an unpopular server and only serve text.

The authoring of web documents is not particularly demanding of CPU and will often be performed on a separate remote machine.

Specific services being provided on the web, for example database searches, may require that the server be on a specific machine.

The level of trust that the providers of the web server have in the authors of the documents being served may dictate specific security precautions that have to be borne in mind. If this level of trust is low then some server facilities may not be available, for example CGI scripts.

Using Simple, Powerful Software

As far as software is concerned, an official service should be based on established software. This limits the choice somewhat, but fortunately the software that is available is very good. Servers running on PCs and Macintosh machines are not considered as these machines are not suitable for most large organisation servers. The choice is limited to either CERN or Netscape Netsite.

Both of these products are easy to install and maintain.

In general terms each of the products supports a common set of capabilities.

The CERN server is freely available. The Netscape product is commercial.

In terms of secure communication the Netscape product is ahead of the CERN server. CERN includes no support for security.

Development work on the CERN server at CERN seems to have stopped. The work has apparently moved to INRIA in France, although there has been no news concerning future directions on the server. As the Netsite server is a commercial product we can be sure that it is tracking upcoming developments.

Maximising network efficiency

A number of recommendations can be made in order to maximise network efficiency.

Every institution should be encouraged to install a cache at their local site. Even if this is very small (say 200Mb) it will keep copies of the most popular pages. This cache should be configured to take advantage of a national cache.

At the moment there is are two well known public caching proxies. One at HENSA Unix and one at Imperial College. All local caches and browsers should be configured to take advantage of one of these caches. In the future it is hoped that more official national caches will come on line. These will be distributed around the country and each institution should make use of the closest.

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