Info about Dns
DNS - Making Sense of the Internet, Domain Names and IP Addresses
Domain Name System or Service or simply DNS is a scheme used to name computers, resources or services that belong to a network. The network could be public like the Internet or private like the networks of organizations. In this system, there is a hierarchical organization that involves a top-level domain, sub-domains and clients, which have corresponding domain names and IP (Internet Protocol) addresses.
This system has three components: servers, content and resolvers. The content refers to the domains. The name server, functions to gather and store names from other servers. The resolvers are the system's clients which pose queries to the name server.
This system is very important because it allows communication between computers and humans and among computers. Computers can only recognize IP addresses whereas humans, perhaps with the exception of computer experts, only understand names in the human alphabet. This is because the human mind makes it easier to remember names while computers are programmed to use the binary code. If there was no DNS, there would be a mismatch and any network would be rendered non-functional.
It simplifies things by allowing the registration and resolution of domain names by computers. Domain names are used to signify ownership or control. People usually choose domain names according to preference and relevance. For instance, a company that markets computers might go for the domain name bestcomputers.com. Through DNS, different users and computers in a network can communicate.
Fortunately, the system is able to assign keep domain names independent of physical location. This is the reason why URLs (Uniform Resource Locator) and e-mail addresses can be used without having to know how the computer will locate them. This is also the reason why there is no need to change e-mail addresses when a mobile phone instead of a computer is being used to access the internet.
While DNS might seem a simple system, it becomes complicated when the magnitude of the Internet is factored in. Millions of people access the internet and change or create IP addresses and domain names daily. Because there are billions of IP addresses in use, there are also billions of DNS requests that have to be resolved every day. Fortunately, the system can handle this by acting as a well-integrated database.
Sometimes, when browsing the internet, a message that “The DNS is down” may appear. This can mean several things. The connection might have been lost and this led to the inability of the DNS to resolve or the server might be down. Other reasons include errors made in the server database or failure of a remote DNS to provide correct data or timely response.
While the system is crucial, it is important to keep in mind its flaws particularly on security. For instance, in DNS cache poisoning, the server is deceived into believing it receives authentic information when in reality, it does not. A server can also be attacked by a virus and this can rebound on millions of Internet users. Using the this system should therefore entail both a sense of awareness and of caution.