Is "www" desirable in web site URL

[Albert Lunde]

> Does anyone know of any advantages or disadvantages of having
> the letters "www" as part of a URL

The short answer: you should do it, but you don't have to choose just one way.

Some historical context:

The "www.domain" convention is an extension of a long-standing set of
practices which pre-date the web and have little to do with "vanity
addresses" that some companies are seeking today.

The original idea was to create easy-to-guess names for network services,
which could stay constant as the actual machines in a site were
reorganized.

You should know that while a system usually has one primary domain name
(the type A record), you can associate a number of other domain names with
it (CNAME records) which act as aliases, that are equivalent for most
purposes.

So, when, for example, my organization, which used to be called ACNS,
wanted to set up an ftp site for the outside world, we didn't use the
actual name of the machine (at least not for long) but created an alias for
that machine called ftp.acns.nwu.edu (home of Disinfectant and
Newswatcher;). That CNAME has been associated with 4 or 5 machines now.
When we wanted to change machines, we didn't have to reconfigure the
machines, just changed where the CNAME pointed in DNS (which takes a day or
two to propagate).

There was usually nothing enforcing these conventions but general knowledge.

For large sites, like universities, this convention distingushes one site
as the primary server for a particular service like ftp, or news, or www,
or network time.

For small sites, this provides room to grow. Once you get beyond one "box",
there are often good technical reasons to put your web server on a
different system than the one whose name was your domain name alone (if
such as system existed).

Now, Netscape has written successively more complex rules for abbreviating
URLs into it's browsers. These are NOT official standards, but they seem
likely to be widely adopted. These give an advantage to site names that
start with "www." for "http://" or "ftp." for "ftp://", and so forth.

I think these are actually good things, in a sense, because URLs were not
designed to just serve the needs of HTTP (the web proper), but to unify
addressing of a half-dozen or more Internet protocols. As such they have a
lot of extra baggage that confuses many people. They were designed to be
printable and e-mailable, but not always simple to memorize.

On the other hand, I think people should learn, along the way, that these
are just short-cuts for the full address (even if they don't know what it
all means.)

(Of course, you can go a long way these days just by pointing and clicking,
without every typing a URL.)

Meanwhile, you can have your cake and eat it too. You can have several
domain names and thus URLs for a web server.

If you are forced to split up the functions of a server at some point
between several machines, you can use a server running redirects to point
traffic at the new server. (Though this is not ideal.)

Also, note... we were changing our campus web server from a Sun to an HP
box some months ago, and thus changing where all the CNAMES pointed to a
new IP address. We put in the domain name changes, waited a short time for
them to settle down locally, and then started running the web server on the
old machine to redirect ALL web requests to the new machine BY IP ADDRESS.
We did this for about two weeks after the change to support a minority of
distant systems, systems behind caches, and such that didn't learn promptly
of the IP address change.


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    Albert Lunde                      Albert-Lunde at nwu.edu