What does DNS mean

Q: What is "DNS"? What is the text of this?

A: DNS, to put it simply, is domain Name System, which is translated into Chinese is the "DNS".

Q: What is DNS used for?

A: In a network of TCP/IP architectures (such as the Internet), DNS is a very important and commonly used system. The main function is to easily remember the domain name and people do not easily remember IP address for conversion. This network host, which performs the DNS service above, can be called DNS Server. Basically, we generally assume that DNS simply converts domain name to IP address, and then uses the IP address found to connect (commonly known as "forward resolution"). In fact, the ability to convert IP address to domain name is quite often used, and when you login to a UNIX workstation, the workstation will do a reverse check to find out where you came from (commonly known as "reverse parsing").

Q: How does DNS work?

A: DNS is used in a layered way to operate. For example: Hit the Lilac station domain name is bbs.hit.edu.cn, this domain name certainly does not come out of thin air, is from. edu.cn the distribution of ... edu.cn from. CN Grant (delegation). Where does CN come from? The answer is from ".", which is called "root domain". The root domain is already the top-level of domain name. and "." This layer is managed by InterNIC (Internet Network Information Center, Internet Information Center). This is what domain name is all over the world, one layer at a A-level grant down.

Q: When I look up a domain name, how does DNS detect its IP?

A: For example, if the domain Name (DNS query) We are looking at today is bbs.hit.edu.cn, the DNS server does the following:

(1) You use the computer (may be a PC, may also be a workstation) to send a problem to the computer set up the DNS Server, ask: bbs.hit.edu.cn IP is what?

(2) This DNS will first see if it is in its cache, if it is, throw out the answer. If not, start at the top. There must be a setting "." On the DNS server. Who to ask. So, this time it goes to "." Layer of any DNS (currently ".") There are 13 units) Q: Who should I ask?

(3) "." The DNS of the layer will answer. CN to WHO to check (and the DNS you use will cache the answer).

(4) Next you use DNS will be to the. CN this layer of DNS asked:. edu.cn to ask who?

(5). CN this layer will answer. edu.cn who to check (and you use DNS also put this answer cache).

(6) Until bbs.hit.edu.cn answer: bbs.hit.edu.cn IP is 202.118.224.2 (and cache up).

After so many processes, finally got the IP, next to make a further connection. Be aware that you will ask a question at each level and write down the answer (cache), and forget (see how long the layer is set to cache).

Q: How do I set up DNS?

A: If you only want to use DNS, you can just set it up in the network properties of TCP/IP. The method you set is related to the operating system you are using. For example, in the control Panel → network → TCP/IP → properties, Windows 9x finds the part of DNS to set up again. UNIX is set in/etc/resolv.conf this file (if, to build a DNS Server, it is not discussed here).

Q: Which DNS data is up-to-date?

A: If you know that DNS is working with a hierarchy, you should know that the closest DNS is the best.