2. “Size of DNS”
Size of the DNS can be describe from the time before it was created all the computer on a network used to receive a host file named HOST.TXT, This files mapped the names to numerical addresses. Due to the fast growth of the network, the HOST.TXT file became unsustainable, Then Domain Name System was invented to replace this method. The DNS server had numerous points of failure for entire internet, for this reason there are multiple root server all over the world. Each label may contain up to 63 characters. (label stands for Sub level domain), The full domain name may not exceed a total length of 253 characters in its external dotted-label specification. In the internal binary representation of the DNS the maximum length requires 255 octets of storage. In practice, some domain registries may have shorter limits.

3. “Introduction”
Domain Name System or so called DNS is the Internet’s mechanism for linking all the host names and IP addresses on the Internet. In Other words, DNS is a distributed and linked system of resolving names to IP addresses. The DNS system is similar to an environment in which all telephone information operators are linked together so that your request can get passed to the appropriate operator. All the URLs that you need to get resolution for on the internet are in a DNS database somewhere. A DNS database administrator has entered the name and IP address into the database. When you use a browser and request WWW refers to a service, and Cnfolio refers to the host name. The .com refers to the portion of the domain name space where this host is found.

4. 3 main Component
Domain Name Server
Domain Resolvers
Domain Name Space

5. “Domain Name Server”
A DNS name server is a computer that runs a DNS server application. That server can store zone file information locally or in memory. A DNS server responds to clients request for name resolution by trying to find those names ( and associated IP addresses ) in name space. A name server also performs database management tasks on the zone files, Such as resource record updates and zone transfers.

6. “Domain Resolvers”
Rather than remember IP addresses, humans find it easier to remember names. Therefore, the names that we use must be resolved to an IP address before TCP/IP can do anything with them. Resolving-or translating-the name to an IP address is called Domain Resover. In other words, A resolver passes name resolution requests between the application on a system and DNS server.

7. “Domain Name Space”
Roots
Top level

8. “Limitation to continue operation of DNS”
Uses 32-bites in every address.
IP version 4 integrated that permits about 3-4 billion users.
10 billion IP addresses as it uses 128 bites for every address.
Mathematically this is a limit resource, but practically it’s an unlimited resource. There should be system for allocation of IP addresses because if anyone wants to starts a business in the internet or if someone wants to have their own private website, they need an IP address and Domain name. And so far, IP address and Domain name are crucial, they are the core resources otherwise there can’t be any communication through internet.
IP version 4
IP version 6

9. “Legislation in the UK for Domain Name System”
In simple words , DNS is not affected by any legislation in the UK because its an International consortium of companies that run DNS server that decide DNS issues. As they can be influenced by British law, overall it plays a small role.

10. “Conclusion”
DNS server are very important for every individual user because not every common human being can remember every unique IP address for each every website , so invention of DNS have made life easier.

11. “References”
Blank, A.G. (2002). TCP/IP JumpStart. USA: SYBEX. Last accessed 01/12/2011.
Wales, J. (2003). Domain Name System. Available: Last accessed 02/12/2011.
Domain Name Services, 2008, online video, accessed 03 December 2011, <
Thomas Lee, Joseph Davies. (2011). Domain Name Service (DNS).Available:  us/library/bb aspx. Last accessed 26th nov 2011.
Bradley Mitchell. (2011). What Is a DNS Server?. Available: stem/f/dns_servers.htm. Last accessed 23rd nov 2011.