How does domain registration works?

Question

I searched Google and Wiki a lot, but I could't find answers for these questions.

1) What exactly registrar company do? They update an root DNS and set there IP of my DNS?

2) How come the registrar can update records in the root DNS? How did they get this priviledge? How could I get this priviledge too?

3) What exactly we pay the registrar for? Just for sending one request to the root DNS?

4) When I register a domain, am I the real (in the eye of the law) owner of the domain? How does e.g. Google protects their domain? Couldn't their registrar just say: "sorry we sold the domain to someone else"?

I hope it's not kind of an offtopic question.

Thanks in advance

Answer 1

1) The registrar has a DNS server. It tells the main (called top-level) DNS server overners (for instance the .com) to forward all requests for yourdomain.com to their DNS server. You can also do this directly with the owners of the top level domain (ICANN in the case of dot com I think). But then you need to run your own DNS server.

2) They don't, see number one.

3) They pay a fee to the top level registrar.

4) Depends on your registrar (possibly country), but with proper registrars you do (however read the contract with your registrar).

Answer 2

Registrars job is basically to coordinate and make sure there are no duplicates in domain names. ICANN manges them. At a technical level registrars (and registries) use the Extensible Provisioning Protocol to achieve this.

They do update the DNS with nameserver information but not the Root DNS servers (which is a totally different area) only the TLD (Top Level Domain) servers.

Legally (I am not totally sure about this, so take it with a pinch of salt) you have a contractual relationship with your registry and from there you can take it to courts and so on. However, starting with ICANN all these organisations (another example is Nominet) have heavily policy based working style and they update them according to the feedback from their customers (us).