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About domain servers - Fiel - 2013-05-25
I'm a total noob when it comes to DNS, so I'm trying to learn.
A:
ME: Sup ISP
ISP: Sup
ME: What's the IP address for thiswebsitedoesnotexist.com?
ISP: Lemme check my cache.
ISP: It's not in the cache. I have no idea.
How does the ISP eventually determine it can't find the DNS record that I want?
B:
ME: Okay, just finished setting up BIND on Metaserver Chinch. How you doing chinch?
CHINCH: Mighty fine, thank you.
ME: How many slave nodes do you have?
CHINCH: A whoooooole bunch
ME: Okay, I want you to tell all of your slaves to tell the world you have the domain Facebook.com and it points to MMIP, my malicious IP. Okay?
CHINCH: Sure.
CHINCH: Hey, Comcast.
COMCAST: Sup.
CHINCH: I have this domain Facebook.com. It points to MMIP. It's the newest record for Facebook.com, and I'm the authoritative DNS server for this record.
COMCAST: Oh, I see then. I must be wrong. Thanks for the update!
ME: Hey, Comcast, I want to go to Facebook.com
COMCAST: Lemme check my cache.
COMCAST: Oh, it's MMIP.
ME: Thanks!
What exactly prevents this from happening?
C:
ME: Okay, just finished setting up my domain on namecheap. How you doing namecheap?
NAMECHEAP: Mighty fine, thank you.
ME: Okay, namecheap, you have the domain foobar.com, and foobar.com points to MMIP, my malicious IP. Okay?
NAMECHEAP: Sure.
ME: Tell everyone you know about this domain.
NAMECHEAP: Okay.
NAMECHEAP: Hey, Comcast.
COMCAST: Sup.
NAMECHEAP: I have this domain foobar.com. It points to MMIP. It's the newest record for foobar.com, and I'm the authoritative DNS server for this record.
COMCAST: Oh, thanks for the update namecheap!
ME: Hey, Comcast, I want to go to foobar.com
COMCAST: Lemme check my cache.
COMCAST: Oh, it's MMIP.
ME: Thanks!
Why does C work but B doesn't?
About domain servers - AngelSL - 2013-05-26
I think you might have more luck if you asked on Server Fault. Or Stack Overflow (though I think this is now considered off-topic)?
About domain servers - Spaz - 2013-05-26
There are 13 root DNS servers. These servers are the ultimate authority on mapping names to addresses. If a DNS request cannot be resolved from cache, it will hit the root servers which will be able to give a definitive answer.
You can't just tell your ISP that you have control over a domain. Only the root servers are trusted with that authority. Also, if you have control over a domain, you are trusted with information about subdomains.
Domain name registrars talk to the root name servers.
It's been a while since I learned this kind of stuff but I think I got the gist of it right. A good networking book will be able to help explain DNS.