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Answer:
1. Why do we need the Domain Name System (DNS)?
Think about a DNS system like a phonebook. For humans, it's much easier to remember the address of a Web site using a name (like flamingflamingos.eu) rather than an IP address. IPV4 addresses (88.151.243.8) were complicated but nothing compared to IPv6 addresses (2001:0db8:85a3:0000:0000:8a2e:0370:7334). So, we came with the idea of using this central database that keeps the relationships between domain names and IP addresses. Also, if the Web site changes address (or host), that is completely transparent to the user because he doesn't know (nor care!) what's the site's address.
2. Given the domain name www.flamingflamingos.eu, what is the top level domain in this name?
The top level of the domain name is the last part of it, like .com, .ca, .net, .org and so on.
In this case, it's .eu. That might mean the Web site has its activities in Europe mostly, depending on how strict the rules of the .eu registrar (organisation in charge of the administration of a top-level) are.
There are basically 3 categories of top-level domains.
There are the country-dependent ones like .ca (Canada), .us (United States), .mx (Mexico) and so on, more or less restricted to their physical location.
There are the original broadband ones, available to anyone, anywhere, like .com, .net .org, .info and so on.
In the recent years, new top levels were created for niches, like .travel, .club, .law, .photo and so on.
3. How many different nameservers need to be visited in order to find the location of www.flamingflamingos.eu, including the ROOT server?
The first step your computer will do is look in its cache, if not found, it will most likely contact the ISP's recursive DNS server to see if someone has visited that Website recently, it will retrieve the IP address from there.
If not, it will first contact the root server to get the address of the top level .eu DNS server and will contact it. It will tell us which authoritative DNS server stores the data for that domain.
We then contact that last server to get the IP address of that Website.
So, we in total we will have contacted 4 servers
4. How long does this whole process take?
Depending on the network capacity and traffic... but that is around 1-2 seconds maximum. Of course, if the data is in your computer cache, there's no delay at all.
5. Once the location is acquired (IP address 88.151.243.8) what does your computer do with that information?
Once the computer has the IP address, it launches a direct connection to that IP address and the desired port (like 80 for Web connections) and awaits the server's response.
Answer:
1) We need the Domain Name System (DNS) because without it, we would need to memorize IP addresses for every site we visit.
2) The top level domain (TLD) of www.flamingflamingos.eu is ".eu"
3) Four name servers need to be visited in order to get the location of the URL www.flamingflamingos.eu
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