Why is WWW necessary in some URLs?

[Guest]

On Wed, 31 Dec 2003 23:11:42 -0600, Richard wrote:

Unless
there's a DNS entry for www.domain, it won't resolve, and you won't be
able to get to it.

Ever hear of a CNAME entry?

 

[JustAnotherGuy]

"www" is not a subdomain of any domain name.

Richard--you're wrong.

ftp.example.com
www.example.com
idiots.example.com

All subdomains.

Honestly, you're wrong. If you'd like some URLs that describe the
concepts I'm sure many would be happy to furnish you with the links.
Would you?

 

[somebody]

Ever hear of a CNAME entry?

Yes, you?

 

[Richard]

How come sometimes it's necessary to use WWW in a URL and sometimes it's
not? This is an example. The first link doesn't work but the second
does.
http://packet8.net/
http://www.packet8.net/

But with other URLs, the WWW doesn't seem to be needed.

I'm using IE6

I'll correct myself just a tad.
It was not a requirement of ICANN, but that of CERN.
CERN initiated the system in 1989.
In 1991 CERN introduced the "WWW" identifier.
Perhaps as a way to distinguish files in hypertext markup from other types
of files.
And also perhaps as a "trademark" of sorts.

What's interesting to note is, that the "domain name" server function was
created 4 years earlier by the university of wisconsin.
The first domain name to come into existance was, oddly enough,
symbolic.com.
As more and more users get connected to the system, technology changes as
well.
Where once we had no choice but to name a file with 8 letters and no more,
we can now use practically any number of letters.

As technology evolved, it became rather redundant to always be typing in the
"WWW" in the address.
IOW, what goes around, comes around.
Servers were given the option of which convention to use.
Which to use to access the page will be determined by the server.
For instance:
http://www.xnews.newsguy.com/
Does not resolve, but http://xnews.newsguy.com/ does.
While on some servers, using either method resolves to the same document.

 

[Guest]

Richard--you're wrong.

ftp.example.com
www.example.com
idiots.example.com

All subdomains.

Actually, you are both (partly) correct. It *could be* a subdomain, or it
*could be* a CNAME. Google the terms and you will understand.

 

[Andrew Cameron]

www.subdomain.domain.com http://subdomain.domain.com

Now that is a subdomain. A subdomain means you can put files into it
and it acts like any directory.

"www" is not a subdomain of any domain name.

If we go by your example (www.subdomain.domain.com), then www.subdomain *is*
the entire subdomain. On the web server config, www.subdomain has been set
up as a subdomain. In your other example, subdomain.domain.com has
"subdomain" as its subdomain.

I could point ftp.domain.com to anyhere - I could even make it my mail
server if I wanted - it just would make more sense to be the FTP since it
has that name. I could create www.www.domain.com and then www.www would be
the subdomain. www is just a "friendly name" saying "this is the website
section of this domain name".

The server doesn't care what subdomain has been asked for - it only cares
what the subdomain resolves to, and on what port you are making the request.
In other words, "www" is a subdomain just like any other.

 

[SteW]

I'll correct myself just a tad.
It was not a requirement of ICANN, but that of CERN.
CERN initiated the system in 1989.
In 1991 CERN introduced the "WWW" identifier.
Perhaps as a way to distinguish files in hypertext markup from other types
of files.
And also perhaps as a "trademark" of sorts.

Or simply as a convenient abbreviation for World Wide Web

What's interesting to note is, that the "domain name" server function was
created 4 years earlier by the university of wisconsin.

To be easier to remember than xxx.xxx.xxx.xxx, useful but not groundbreaking

The first domain name to come into existance was, oddly enough,
symbolic.com.
As more and more users get connected to the system, technology changes as
well.
Where once we had no choice but to name a file with 8 letters and no more,
we can now use practically any number of letters.

On MSDOS (and some others) but not on all OSs and not on those typically
used as servers

As technology evolved, it became rather redundant to always be typing in the
"WWW" in the address.

It was never necessary unless someone had set www as a subdomain
Many browsers will add http:// if it is not included but not www

IOW, what goes around, comes around.
Servers were given the option of which convention to use.
Which to use to access the page will be determined by the server.
For instance:
http://www.xnews.newsguy.com/
Does not resolve, but http://xnews.newsguy.com/ does.
While on some servers, using either method resolves to the same document.

newsguy.com is the domain, it resolves
xnews.newsguy.com is a subdomain of newguy.com, it resolves
www.newsguy.com is another subdomain of newsguy.com, it resolves

Don't know whether or not a sub-subdomain (eg www.xnews.newsguy.com) is
allowed or not, but it won't resolve unless web server and name servers
have been set up for it. It is for this reason that
www.xnews.newsguy.com will not resolve.

Ste W

 

[Toby A Inkster]

Ever hear of a CNAME entry?

A CNAME entry is a subdomain, the same way that an A entry is a subdomain:

www.goddamn.co.uk CNAME goddamn.co.uk
-or-
www.goddamn.co.uk A 81.2.120.180

Both are equivalent. They both establish a subdomain "www" of
goddamn.co.uk and point it somewhere.