THE LARGEST NAME SERVICE ACTING AS A PHONE BOOK FOR THE INTERNET The Domain Name System click here to next page 1

THE DOMAIN NAME SYSTEM  There could not be an existence of the internet if the Domain Name System (DNS) was not available. This is because it converts domain names in to Internet protocol addresses (IP Addresses) and IP addresses back to domain names. This function makes the DNS to act as a phone book for the internet.  DNS can be defined as a type of naming system for services like computers that are connected to the internet[what is DNS, ]. Domain names are assigned by the Internet registry and there examples include; google.com, yahoomail.com and a lot more. These names help one to find their way round the Internet easily since they are very easy to remember and use. All domain names have a suffix like net, org or gov which show their top level. click here to next page 2

SIZE OF THE DNS  The DNS User Datagram Protocol (UDP) has a maximum limit message size of 512 Octets. The limit is due to the required minimum internet protocol reassembly limit of the IPV4 but is used as the DNS protocol limit. There is an Extension Mechanism (ENDS) for DNS protocols that helps to permit large responses. The DNS responses includes requests or a copy of a request, and have available space which is more or less than the full 512 octets. These responses include; negative responses, positive responses and referrals but, negative responses are smaller than positive responses and referrals. for positive responses and referrals, every octet must be well allocated. [ DNS Referral Response Size Issues(2011) ]  If the UDP response total size exceeds 512 Octets, then the size in the ENDS or the data required is very large, A request will have to try again using the Transmission control protocol (TCP) depending on the information required or omitted. click here to next page 3

HOW THE DNS WORKS  There is a server that provides the services of the DNS called the DNS server by resolving and updating IP addresses. when we type a domain name in to the browser, its translated in to an IP address through a process called resolving the domain name which is done by the hierarchical name servers. This process occurs when a request is made or a domain name is typed in to the browser and sent to the DNS Resolver. The resolver has a cache that consists of recent used information, where some answers can be found. But, if the cache does not have the answer to the request, the resolver will then send the same request to the server which will locate it to the necessary IP address. when an answer if found, its saved in the cache for future use and also sent to where the request came from. To find the answers, the system goes through many steps which shows that its hierarchical. click here to next page 4

COMPONENTS OF THE DNS Namespace  The namespace allows a name to be put in a tree structure which has a high level domain and the root nodes. Each node on the tree is a domain name (DNS (Domain Name System) (n.d)). The tree has a unique host which is the name given to the end of a branch that corresponds to an entity on a network. Each level on the tree shows a leaf or a branch. A branch is when more than one name is used to show different named resources and a leaf shows a name being used one at a time at a certain level to show a specific resource. Server  Also known as the name server and helps clients find information In the DNS tree. Can set information about any part of the domain tree. Regarded as the authority for the parts of the name space and helps to provide a link between IP Addresses and the DNS. It forms a connection or link between an IP address and the domain names. There are both primary and secondary servers. Commonly used servers are called the Berkeley Internet Name Domain (BIND) (Domain Name Service (n.d)). Resolver  In the DNS, the resolver is on the client side and responds to clients by getting information from the name server. Has the ability to access more than one server and user datagrams directly. Clients which are responded too can be called user programs and, are in the form of subroutine calls or system calls. Click here to next page 5

FUNCTION OF THE SYSTEM  When queries are asked, the domain name provides the information needed. When you browse a certain website, the system goes to the destination required just like a telephone. These functions help to show that the DNS is very reliable.  The DNS helps to translate numerical names to IP addresses for things like mailboxes and webpages that are very easy to remember, memorize, recognize and are readable. It is very easy for some one to remember than its numerical name which is ( ).  Has a domain namespace which consists of a tree with nodes and branches that have a resource record used to hold information associated with domain names. It also has a name server that helps clients to find information on the domain name tree and a resolver that responds to clients.  Can assign domain names to many internet resources and users in a way which is meaningful independent of its location. This helps the internet contact information and the world side web (www) hyperlink to remain consistent although any changes take place. Click here to next page 6

LIMITATIONS OF THE CONTINUED OPERATION OF THE SYSTEM  The underlying protocols are not very secure, this is because of the lack of authenticity and integrity checking of data in the DNS that causes threats to its functionality. But, the Internet Engineering task force (IETF) created a working team that will add DNS security extensions to its existing DNS protocols.  Domain names used in the DNS have no spaces, cannot use special functions like an exclamation mark, have a total number of characters of about 63. In some places, a few characters slightly more than 63 can be used. Click here to next page 7

IF THE OPERATION IS AFFECTED BY ANY LAWS IN THE UK  Users being can access the internet from various places around the world and information travels through many places to reach its destination. This information includes; private information, personal information, company secret formulas and business information. So, there should be laws or regulations to protect that information in order to prevent theft, terrorism threats, trade mark abuses, and protect copy rights. ( Legal Issues on Domain Name: A World Wide Watch (n.d))  Its not very easy to investigate these crimes since criminals who do all this use stolen credit cards and false details but, there are some registries like the the Nominet that requires their registrants to give accurate information and can disable those registrants who cannot live up to the registration accreditation agreements, this can help keep control over the domain names. ( Law enforcement push for stricter domain name rules (2010)  The Regulation of Inventory Act 2000 which allows new technologies like the internet to be monitored is one to the legislations that affects the DNS. This Act is used to monitor things like identity thefts, terrorism threats, and a lot more. (Internet Rights(n.d)).  The Security Service Act 1996 is another legislation in the UK which gives the security service the function of acting in support of the prevention of serious crimes. There are lots of crimes carried out on the internet, some of which include, identity theft and terrorism threats.  The other act that affects the DNS is The data protection act 1998 which is about the protection of personal data(Internet Rights(n.d)). Personal data refers to things like; criminal history or justice, health care records, financial transactions and a lot more. The DNS is also affected by this act since it is the back born of bank card payments and ATM machines. Click here to next page 8

CONCLUSION  The DNS which was primarily designed to replace a host table but become a database for the Internet is indeed the largest name service acting as a phone book for the internet. It converts domain names to IP addresses and IP addresses back to domain names. This system works on services like computers, has a size of about 512 octet, and has components like the namespace, name servers and resolver. It has limitations like the lack of space and special functions in its names, has less number of characters, and its security is not very good. Click here to next page 9

REFERENCES  what is DNS( ). Retrieved from  DNS( Domain Name System) (n.d). Retrieved from  Domain Name Service (n.d). Retrieved from  Internet Rights(n.d). Retrieved from  DNS Referral Response Size Issues(2011). retrieved from (Legal Issues on Domain Name: A World Wide Watch(n.d)retrieved from  Law enforcement push for stricter domain name rules(2010) retrieved from Click here to next page

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