Domain Resolution and URL Processing

A domain name is an address that is used to access any website. Domain Name is unique in nature and it is very easy to remember. By typing the Domain Name user can reach the website whichever he desires. The actual address of any website is very complicated but with the help of Domain Name, this complicated address can be converted into a simplified human-comprehensible form. Domain Name is formed with the help of rules and procedures of DNS.

Why Domain Name is Important ?

The domain name is easy to remember but the IP address is not. Let’s take an example of the telephone directory, we don’t remember the phone number of the persons we just remember the name of the person and then search the number using their names, not with their phone numbers. An IP address can be changed in the back-end but the domain name remains the same.

History: We are using the Human Comprehensible form of the host’s numerical address since the ARPANET era. Earlier each computer on the network used to retrieve host files from the computer at SRI which used to map computer host names to numerical addresses. As networking started to grow rapidly henceforth it became nearly impossible to perform the task with traditional methods and therefore in 1983, the Domain Name System was introduced on the ARPANET.

Characteristics:

• The shorter the domain name then it’s easier to remember and understand and the longer the Domain Name it’s hard to remember and understand therefore keeping Domain Name short and crisp is advisable.
• Domain Name should be easy to spell because the user won’t be able to remember it correctly if it’s complicated.
• In Domain Name .com extension is most popular as many people remember the sites with this extension and tend to forget other extensions.
• Sometimes Domain Name will not have any meaning but it becomes so popular that people recognize that domain name just by listening to its name, so we can also create a brand, and we don’t really need any meaning unless and until Domain Name becomes a brand.
• Domain Name ideally should not contain hyphen and numbers as it becomes cumbersome to remember.

Steps for Domain Resolution and URL Processing: 

When we type a web address into a web browser, our computer needs to convert them into an IP address. So that it can contact our web server and delivers to you. This is called a forward lookup because we are converting a hostname into an IP address. It is also called a reverse lookup when we are converting an IP address into a hostname.

• First, we will type the name of the website which we want to access. For example — facebook.com.
• Then this domain name will map into their corresponding IP address, and the conversion of the domain name to IP address is the responsibility of the resolver. There is a resolver between request and root server.
• The website request first goes to the root server, it can be done by 2 methods either with a recursive method or with the iterative method. There are a total of 13 root servers all over the world.
• The resolver then gives an IP address of the next level to the resolver. The next level consists of generic servers or country servers.
• The resolver resolves the domain name from right to left means in our example it will first resolve “.com”. Then “.com” gives a link to the resolver after that our request will be forwarded to the Authoritative Server.
• Authoritative Servers stores all the IP addresses and names. There can be multiple IP addresses of a particular website. Facebook has more than 70 thousand servers hence the IP address can be multiple.
• This IP address is given to the resolver and then the resolver gives that IP address to our computer. Then we can access the data in our computer.

These steps are only performed when we access any website for the very first time. When we access that website a second time then our request is not forwarded to the root server because our internet service provider(ISP) cached that IP address so that whenever you need to access that website, it will provide IP address easily.

Advantages:

• Good Domain Name adds credibility also it separates from other Domain Names.
• Also, Domain Name gives visibility to the brand and it also attracts many users.
• Domain Name can increase search engine ranking once it becomes popular among Internet Users.
• Domain Name establishes a unique identity in cyberspace.
• Domain Name can be resold, leased, and bartered which is also one of the great advantages.

Disadvantages:

• DNS registry can only be controlled by ICANN which is a big challenge as it’s tied to only one country and henceforth it also challenges Net Neutrality.
• In DNS server-side only see the IP address and henceforth it can be manipulated by hackers.
• Also, the DNS server is based on the slave-master relationship which is another challenge.
• In case the host starts malfunctioning then it becomes hard to access the web page.
• In many instances, the hacker’s target server machine and makes the user redirect to another webpage which results in phishing.