"www" Needed Somethimes?

[shanenin]

I noticed some sites need me to type in http://www.sitename9.com and others allow just http://sitename9.com . Why is "www" needed sometimes? This would seem like a huge negative to that site losing traffic.

here is an example:

http://rochestersign.com

http://www.rochestersign.com

my domain brighteyedcomputer.com will work with or without the "www" prefix

Edited July 27, 2007 by shanenin

[Matt]

By default, all popular Web browsers assume the HTTP protocol. In doing so, the software prepends the 'http://' onto the requested URL and automatically connect to the HTTP server on port 80. However, for whatever reason, many servers require the www subdomain. The www subdomain is redundant and time consuming, but it is simply that many servers need it.

In most cases, example.net and www.example.net are both valid methods of reaching this website. Many servers default to this. In others, www.example.net is a valid address, but it redirects all traffic to example.net. In your issue, it appears, they require the www. It's simply based on how the server is configured.

Something you might find interesting: http://no-www.org/

[shanenin]

I would be really upset if my site required "www". I think I would be losing business. I was pricing out signs for my business and kept getting dead links. I thought all of these sign companys had broken sites. They lost out on potential business. Then my wife tells me, the computer guy, you need to type "www" first for some sites. You learn something new all the time.

Now I am off to read the link you posted :-)

Edited July 27, 2007 by shanenin

[mikex]

I am in the habit of usint ctrl + enter to auto fill the www. and the .com

ctrl + shift for www. .net

M

[DanielSmith]

Good quetion and good answers!

[Hai-Etlik]

The www is not indicating the protocol; that's what the scheme portion of the URL ("http") is doing.

"www.sitename9.com" is a DNS name which in the context of the URL is being used as a hostname. The web browser simply doesn't care about the structure of DNS names, and doesn't even really need to know that it IS a DNS name as it just passes the hostname to the resolver in the OS. So as far as your web brower is concerned, the www is no more meaningful than any other part of the hostname.

Now DNS names are hierarchical. Once you have a name, you can create as many sub names as you want and do whatever you want with them. You can do a lot of different things with them, using them as hostnames is just one, and hostnames don't need to be confined to those hosts running web servers.

So if you have a bunch of machines, and one domain name, you will probably want to give each host a name under the domain name you have. If you follow convention, the real names will be meaningless things unrelated to the location or use of the machine in question, but you will want aliases that are based on their use. Like www for the machine running the public web server. So www.whatever is saying "the public web server of whoever controls the whatever domain." Now you can associate an address with a domain and still have subdomains, and since the most common use of DNS at the moment is web hostnames, it's common to use the highest name for the web server.

There has been an addition to DNS that is supposed to make all of this work better called the SRV record. It lets you associate different services on different hosts with a single name. And a service can be provided by several hosts. It also dispenses with the need for standard port numbers (You can have two web servers on a host without needing to include a port number in the URI). Unfortunately, SRV records are very poorly supported by applications (None of the major web browsers support it)

[Phil]

The primary purpose of 99.9% of domains today is for pointers to sites on the world wide web. The www. prefix is left over from the days when this was not the case. Each prefix would have pointed to a different server - e.g. www. ftp. mail. etc.

The www./non-www. system plays havoc with SEO. It is apparently better to redirect the non-www. to the www. (e.g. mysite.com to www.mysite.com) using the HTTP 301 response and the Location header.

Phil