Exercise4-1

4.1.) Describe the IP protocol. What is DNS?

Cisco(2009) states that IP is stand for Internet Protocol that is a network-layer (Layer 3) protocol of OSI model (Open Systems Interconnection Reference Model), it contains addressing information and some control information that enables packets to be routed. Along with the Transmission Control Protocol (TCP), IP represents the heart of the Internet protocols.

Cisco(2009) also state that IP has two primary responsibilities: providing connectionless, best-effort delivery of datagrams through an internetwork; and providing fragmentation and reassembly of datagrams to support data links with different maximum-transmission unit (MTU) sizes.

Webopedia(2009) states that DNS is stand for Domain Name System (or Service or Server) that is an Internet service that translates domain names into IP addresses. Because domain names are alphabetic, they're easier to remember. The Internet however, is really based on IP addresses. Every time you use a domain name, therefore, a DNS service must translate the name into the corresponding IP address.

For example, the domain name www.example.com might translate to 198.105.232.4.

References:
Cisco(2009). “Internet Protocols”. Received 18th March, 2009 from URL - http://www.cisco.com/en/US/docs/internetworking/technology/handbook/Internet-Protocols.html#wp4145
Webopedia(2009). “DNS”. Received 18th March, 2009 from URL - http://www.webopedia.com/TERM/D/DNS.html