IS THE "www" still neccessary in URLs Addresses?

[~0]

www?

[redcircle]

It's not necessary but people are used to having the www in front. The www is just a subdomain reflecting that you are going to be using the httpd service on the machine. It is an organizational method.

www = web
ftp = file transfer
mail = mail server

Just makes life a little easier.

[OSFan]

I am lazy when it comes to typing URLs, I miss the www by default.

This mostly gets me to where I wanted to, but on the rare occasion, it wont, and I have to add the www to get into a website. My own website is accessible by both.

[williamjay]

Howdy,

When a domain is registered, it requires the services of two Domain Name Servers. DNS Servers allow a name to be resolved into the ip address format. Browsers generally hide the workings of this name to address and back translation. In the Windows® registry are entries for what will be prepended when a user inputs an address for the browser to locate. things like http://, http://www., ftp://, and etc. These generally find the named URL, but fail when the names tried don't exist in the DNS database for a given domain.

Typically, when a domain is registered, at least one 'A NAME' record is created in DNS, which points to an ip address. Very often, a 'CNAME' record is also created, for www, which points to the name .whatever_is_the_actual_domain_name.com contained in that 'A NAME' record. The difference here is that an 'A NAME' points to an ip address while a 'CNAME' points to the name contained in an 'A NAME' record. A single ip address can have several 'A NAME' records, and a single 'A NAME' record can have several 'CNAME' records pointing to it. That's why the typed URL 'domain.com' will work in a browser when 'www.domain.com' fails, because the former is always created and the latter is an add-on. This assumes that webserver software is actually running on the machine at the ip address contained in the 'A NAME' record. . .

William

[OSFan]

Why do I think that might go over many peoples heads! I had to read it a few times to get my head around it.

That's why the typed URL 'domain.com' will work in a browser when 'www.domain.com' fails, because

Isn't it more of the case that domain.com files, and you have to go back and put the www. in? I have seen, however, sites that work only without the www. www will always be a subdomain made, because we are all used to typing www.site.com. Simply saying its just a waste of 4 bytes, would wreck the internet linking!

For my own website, the www. is required unless I go back and ask for it to work without, but this is down to virtual hosting, which is quite common today.

[Renaissancewoman]

Like all machines, computers are tempermental. Sometimes the "www" is not needed sometimes it is.
But there are more specifics behind that and also it depends on the system and network you are using.

[williamjay]

OK, point taken about the above description, accidentally on purpose a bit twisty to enumerate some of the complexities of this issue.


Assume that there is a web server running at the ip address indicated for www.


If the DNS chart for a domain looks something like:

A NAME -- domain.name. -- 127.0.0.1
CNAME -- www. -- domain.name.

-> then http://domain.name/ and http://www.domain.name/ will both resolve to the same place. --> Not Required www.


If the DNS chart looks like this instead:

A NAME -- domain.name. -- 127.0.0.1
A NAME -- www.domain.name. -- 127.0.0.2

->then the two are pointing to two different locations. --> Requires www.


If one uses a hosting service, then the chart may look like this:

A NAME - domain.name. -- 127.0.0.1
A NAME - hosting.domain.name. -- 127.0.0.2
CNAME - www. -- hosting.domain.name.

->then the two are pointing to two different locations. --> Requires www. or hosting.

William