[description], Story, any other text you want to use.
by: Clare Lawrence
How to understand the Domain Name System
Ever wonder why DNS systems came into existence? Efficiency. Every computer has a distinct IP address, and the Internet needed an elite method for obtaining these addresses and for managing the system as a whole. Enter ICANN.
The Internet Corporation for Assigned Names and Number manages the DNS root of the Internet domain namespace. ICANN's role is to manage the assignment of identifiers, ensuring that all users have unique names.
The DNS system is run by a series of servers called DNS servers. ICANN manages the root DNS domains, under which are the top-level domains.
It also manages:
- Organizational domains
- Geographical domains
- Reverse domains
Beneath the top-level domains are other naming authorities such as Nominet, the UK's naming authority.
How does a DNS Query work?
The process occurs in two parts. Firstly, a name query begins at a client computer and is passed to DNS client service for resolution. When the query cannot be resolved locally, DNS servers are queried.
For example, when a web browser calls the fully qualified domain name www.discountdomainsuk.com, the request is passed on to the DNS client service to resolve the name by using locally cached information. If the query is held in the cache, then the process is complete.
If, however, the query cannot be answered locally, the DNS client service uses a server list (ordered in sequence) to query external DNS servers. When a DNS server receives a query, it first checks to see if it is authoritive for that domain name. If it is authoritive, it resolves the name, and the process is complete.
If the DNS server is unable to resolve the query, it in turns queries other DNS servers, using a process known as recursion. DNS servers make use of root hints to assist in locating DNS servers, which are able to provide the required result. In this way, DNS queries are minimised and the Internet is able to operate quickly and effectively.
A typical query may run as follows:
Client contacts Nameserver A looking for www.discountdomainsuk.com.
Nameserver A checks its cache, but can't answer, so it queries a server authoritive for the Internet root.
The root server responds with a referral to a server authoritive for the .com domains. NameserverA queries the the .com server and gets referred to the server authoritive for www.discountdomainsuk.com.
Nameserver A queries this server and gets the IP address for www.discountdomainsuk.com.
Nameserver A replies to the client with the IP address.
Queries can return answers that are authoritive, positive, negative or referral in nature. In the event of a negative answer, another DNS server is queried.
By Clare Lawrence 13th August 2004
About The Author
Clare Lawrence is CEO of Discount Domains Ltd – A leading UK provider of Domain name registration and Web Hosting services. Please feel free to re-publish this article provided this reference box remains together with a hyperlink to http://www.discountdomainsuk.com Clare can also be contacted on email@example.com.
satellite dish network
Real Time Media On The Net
This is one of the best resources for information on Real Time Media On The Net you can possibly find.
Follow our links to find more information on Real Time Media On The Net.
We hope that we have all of the Real Time Media On The Net details that you could need.
Real Time Media On The Net
Indexing is simply the work the Search Engine Robots do to give you information on satellite dish network. How does an indexing robot decide what to index? Well they just send their Bots or Spiders to crawl the web looking for satellite dish network on web sites.
If an indexing robot finds a document that contains satellite dish network, it may decide to parse it, and insert it into its database. How this is done depends on the robot. Some robots index the HTML Titles that contain satellite dish network and keep them in their database. Others will look for satellite dish network in the first few paragraphs, or parse the entire HTML and index all words.
Real Time Media On The Net Index