Have you ever wondered how the internet works? Have you ever come up with the question of what happens behind the scenes once you type the web address of a web browser? So with this, we would like to take the initiative to share our knowledge of one of the mechanisms that allow us all to browse the web easily.
The mechanism we mean is Domain Name System, commonly known as DNS abbreviation. In short, DNS works like a phone book (yellow pages). For example, when you make a request to get access to our web site, amanz.my, your request was first made to the DNS server before you got to our website. The question is, why should your request be answered by the DNS server? In other words, why is your request not made directly to our web server?
Name and Number
To answer the above questions, we should review the basic of the internet infrastructure. To revise the internet structure, we need to borrow Time Stone to bring back to 1983 to meet Paul Mockapetris at the University of California Irvine (UC Irvine) when the internet is known as ARPAnet.
In general, every unit of computer within a network has a unique address. For example, when computer A is connected to a single network together with computer B and computer C, each computer unit will receive their unique address. Computer A will get address 192.168.0.2, computer B as well with address 192.168.0.3, and computer C with address 192.168.0.4. If computer A user wants to connect to computer C, computer A should use address 192.168.0.4 to interact.
This address is known as IP, an abbreviation to the internet protocol. An IP address is a numerical label assigned to each device that is connected to the computer network. It has two main functions: to provide identity to the device (such as identity card number) and location within the network (such as two numbers referring to state in the identity card).
Initially, the use of IP addresses is not as complicated as the number of devices in the network is still low. However, as the network grows and the number of devices increases, it becomes difficult for users to memorize IP addresses to access devices on the network. If you’re a handsome young man in the late 90s, you know how hard it is to call the girls because you need to memorize many phone numbers.
But if you are handsome and smart, you will keep the girl’s phone number in the 555 booklet. Believe it or not, this is the initiative taken by early internet users before 1983. Currently, address mapping is done manually by sharing a document known as host.txt. This document maps IP addresses with names that are easy to memorize.
When sharing hosts.txt documents became commonplace among ARPAnet users at the time, Paul Mockapetris then realized that this practice might not be practical for the future. Imagine that every day we need to download the hosts.txt document every morning before surfing the internet, of course, it is a problem for all internet users.
To solve this problem, Mockapetris suggests that address mappings need to be centered, enabling mapping to happen automatically. This proposal is based on the rationale that the computer network at that moment is rapidly developing, then the mapping system should be centralized, agile, dynamic.
The next question is how does automatic mapping work?
If the hosts.txt document keeps a list of all IP addresses and needs to be updated manually, mapping automatically simplifies the process by submitting the mapping assignment to another entity. This is the concept that forms the DNS service technology. In summary, the DNS service has two main tasks: (A) keeping a list of IP addresses and (B) helping the devices communicating with them to map the IP address. With the existence of a DNS service, users no longer need to memorize IP addresses and devices within the network can be accessed by using the domain name (domain name). For example, the user only needs to type the domain name wikipedia.org and then the DNS service will map the domain name wikipedia.org to IP address 18.104.22.168.
To facilitate understanding, DNS has similar functions like Heimdall and Bifrost Swords to connect the nine realms of Asgard. If the user (Thor) wants to gain access to an Asgard website, the user simply calls the web domain (“Heimdall, take me home to Asgard”). DNS servers have a database that stores a list of all IP address websites, just like Heimdall’s capabilities that have visibility beyond space and time. Then, DNS will translate the instructions to the IP address (location coordinates) to allow the user (Thor) to access the site (Asgard).
With the help of Heimdall and Bifrost Swords, Thor does not have to bother to open the door dimensions like what Doctor Stephen Strange needs to do which opens the dimensions door to require some extra time and equipment.