DNS question?? please help?

When you request a web page (eg. example.com) your computer first looks in its hosts file to see if the domain name is located there if it doesn't find it there it then "contacts" whatever dns server your using (most people use their ISPs DNS servers so I will assume that is what you are using) so your computer basically sends a request to the DNS server (DNS runs on UDP port 53). The DNS server then either replies with the ip address of the DNS server if the domain has been looked up recently the DNS server will store the ip address in its cache or if the domain name is not stored in its cache then the DNS server will lookup the authoritive dns servers for that domain then "contact" them and ask them for the ip address of said domain then the authoritive dns servers will tell your dns servers the ip address of what ever domain you wish to lookup and then your dns servers will then tell you what the ip address is. Your computer then contacts the web server.

I recommend using OpenDNS because of its speed and security features.

OpenDNSs DNS server ip addresses are

208.67.222.222

208.67.220.220

See these 3 podcast transcripts of Security Now that explains all this TCP/iP business;

https://www.grc.com/sn/past/2006.htm

#25, 26, 27

It goes through your ISP. The ISP has the host lookup table that is used, this assumes we are at home, not the office.