Port 53 (tcp/udp) :: SpeedGuide Internet Firewalls: Frequently Asked Questions - Interhack Traceroute, Ping, Domain Name Server (DNS) Lookup, WHOIS User Datagram Protocol – Wikipedia networking - Why should I use DNS ? - Super User 4 Reasons Why Using Third-Party DNS Servers Is More Secure networking - When is it appropriate to use UDP instead of What is a DNS leak and why should I care? Develop a basic DNS server (in C#) - Stack Overflow Allow Both TCP and UDP Port 53 to Your DNS Servers What is a DMZ, and why do I want one? ``DMZ'' is an abbreviation for ``demilitarized zone''. In the context of firewalls, this refers to a part of the Das User Datagram Protocol, kurz UDP, ist ein minimales, verbindungsloses Netzwerkprotokoll, das zur Transportschicht der Internetprotokollfamilie gehört. Possible Duplicate: Google's DNS service: Google public DNS I was asked to put as an alternative DNS server. Through whois I found that the What is a DNS leak and why should I care? When using an anonymity or privacy service, it is extremely important that all traffic originating from your Allow Both TCP and UDP Port 53 to Your DNS Servers DNS queries are getting bigger so we do not want to accidentally block them Free DNS tools: ping, lookup, trace, spam blacklist check, etc. Why is changing your DNS a good idea? What security benefits does it bring? Can it really make your online activities more secure? Since TCP guarantees packet delivery and thus can be considered reliable, whereas UDP doesn't guarantee anything and packets can be lost. What would be SG Ports Services and Protocols - Port 53 tcp/udp information, official and unofficial assignments, known security risks, trojans and applications use. I am developing a very basic DNS server for my own purpose. The way I understand it, the DNS server receives UDP packets containing the requested domain