How Internet Url Addresses Work?

URL is an acronym for Uniform Resource Locator. As the name suggests, URL locates the resources or web pages you look for through your browser. A resource can be anything like an HTML web page, an image, a CSS document, a PDF file, or a website. To access these resources, you need their IP addresses because a browser connects with those resources through an IP address. Therefore, the URL is basically the same thing. Every resource has a unique IP address, and it is necessary to distinguish it from the other resources of the same kind. Often URL has been interchangeably used as a web address. This is because it contains the actual location of a web page on a web server.

What a URL actually does?

A URL helps you to access a resource on a particular network. It is a text used without spaces. When it is entered into the address field of a web browser provides the desired web page. As a matter of fact, every website has a unique IP address. To access that website, we need to know its IP address(which looks somewhat like 78.124.556.10). This kind of numbers is really impossible to remember for every website that you wish to access. To handle this kind of situation URL is used. There is no need for remembering a lot of complex IP addresses for every website. You just have to keep in mind the URL of the website you are looking for. The URL contains certain components that help the browser to retrieve the resource information from a web server. These components form a complete URL address.

Let us first have a look at the components of a URL, then we will go for the mechanism behind it.

Components of URL

A simple URL looks like:

http://www.contentwriting.org:80/my_article

• PROTOCOL(https):- It is the first component of any URL. The protocol defines the set of channels that must be used to exchange or transfer data on a computer network. The most common of all the protocols being used today is HTTP (Hypertext Transfer Protocol). Others include FTP://, TELNET://, MAILTO://, IRC://, GOPHER://, etc.

• DOMAIN NAME:- A domain name represents the name of the resource or particularly the website that is requested. To avoid the direct usage of (IP Internet Protocol) addresses, domain names are used. These domain names are then converted into their corresponding IP addresses by DNS (Domain Name System) servers for a computer to understand the request.

• PORT:- Port number represents the "GATE" which is required to access the requested resources on the internet. Some of the standard ports include 80 and 443 for HTTP and HTTPS protocols respectively. If any of these protocols are being used for transfer of information, then there is no need to specify the port number in URL. But, if any other protocol is used apart from HTTP/HTTPS then it must be stated.

• PATH TO THE FILE:- This section of the URL specifies the particular path that must be followed to locate the resource on the web. Earlier, the path was represented as a physical location on the web. But now, it is handled by the web server itself as an abstraction.

• PARAMETERS:- A parameter is extra stuff which the web server uses to access the resource. Using this extra information provided in the URL web server returns the resource location to the browser. The parameters are separated by a special symbol %. Since spaces are not allowed in the URL, therefore, % is used for separation between various texts. Every web server uses its unique set of rules to handle parameters.

Now when you are clear with the main components of a URL, let us develop an understanding about the working of a URL address on a browser.

Working of a URL address

We use URLs to simplify our search by replacing an IP address with the domain name of the resource we are looking for on the web. This makes it easier for us to give the exact location of a resource in the address bar of a browser. But we need to communicate with the computer in a language that is compatible with its compiler. That is, for a computer to locate the correct resource for a requested web page it is necessary to provide the IP address of web page. So, how does the IP address is retrieved from the domain name of the resource? The DNS server does this task for the computer. It converts the domain name present in the URL into the corresponding IP address of the web page. Then the computer, with the help of this IP address accesses the requested web page. There are a series of steps involved in the process. Let us have a brief description of the same.

• The user enters a certain URL into the address bar of the browser. The URL contains the domain name of the requested web page.

• A request is sent to the DNS server through an Internet Service Provider who caters internet services to the user. This request is carried by a router.

• The DNS server converts the URL into the corresponding IP address of the web page that the user requests. If the DNS server finds the correct IP address it returns the same to the browser.

• The browser now has the IP address of the requested web page. It sends a request to the external web server to get data from it.

• The web server provides the intended HTML data stream to the browser on its request.

• The browser, in turn, furnishes this HTML piece of code into a visible web page that the user requested to see. Hence, the web page is displayed on the screen through the URL provided by the user.

So, this was all about how the URL addresses work. Above mentioned steps represents the entire flow right from the user opening the browser window, typing the URL address of web page and the displaying thing.