Today, I signed up for a web host at JustHost, and registered for my domain name at NetFirms. JustHost told me to enter NS1.JUSTHOST.COM and NS2.JUSTHOST.COM as my DNS Namespace at NetFirms to redirect the website to point to my JustHost server. My question is how would NetFirms understand which account at JustHost is mine as I provided a general address that did not contain any information about my account?
I apologize if I have used any incorrect terminology as I don’t quite understand exactly how the internet works yet.
What you entered is the DNS server information. The web hosting company already know which IP address(es) they put you on, and that’s all that DNS does; resolve host names to IP addresses (and vice versa, if they set you up properly). The domain registrar doesn’t care where your web server is (or even what sort of services you offer; it could be SMTP, or IMAP, or several, or none at all); all they need to know is where to send those who want to ask.
Once someone who obtained your IP address from the DNS server connects to the www server on that IP address, the client sends the URL it is requesting, which is then resolved by the server. (The original HTTP spec didn’t include the host name part of the URL in the request, so technically the request puts the host name part in the
Host:attribute if the request, not the main request line. I don’t imagine this detail has any significance for you, but in case you will be reading up on virtual hosting, this might help understand it.)