Address Resolution Protocol (ARP)
One of the most important protocols in the TCP/IP suite is the Address Resolution Protocol (ARP). It is used to map an internet protocol (IP) address to a physical machine address (MAC). This is recognized in the local network of an IPv4 network. The ARP normally requires all receiving hosts to associate their IP addresses with the ARP request. As a result, if host one sends a random IP packet to host two, host one will look up the router1 MAC address in the ARP database (Fischer et al., 2003). A security issue will arise since the replies to requests are sent in a broadcast manner. The attacker will send a rejoinder with fake MAC address of another host and thus unwittingly get traffic intended for that host.
Difference between global and private IP addresses
The global/public IP address is apportioned from the Internet Service Provider (ISP) when connected to the internet. This address is sent along by the web browser when requesting a web page (Clark et al., 2005). The ISP will use this to know which specific client required a precise webpage. The local or private address is automatically assigned to the computer or device when connected to a router. This address is concealed from others and is merely used inside the network. There are three IP blocks set aside for internal use, and they are class A, B, and C.
How a gateway converts a private IP address into a global IP address using NAT/How this is important to us in today’s information technology environment
Internet applications that necessitate Network Address Translation are equitably complex and transpire briskly that the end user seldom knows they occurred. A workstation in a network makes an appeal to a computer on the internet. Routers in the network recognize that the request is for resources outside the network, hence send it the firewall. The firewall perceives it through internal IP (Coley & Wesinger Jr,2000). It then makes the application using its public address to the internet and returns the response to the computer inside the private network from the internet source. It provides security because only the global address is seen on the external interface of gateway firewall. It will deter those with malicious intentions from targeting the computer with attacks.
References
Fischer, J., Anastasiadis, C., Chan, H., & Watkinson, D. (2003). U.S. Patent Application No. 10/411,264.
Clark, D., Lehr, W., Bauer, S., Faratin, P., Sami, R., & Wroclawski, J. (2005, September). The growth of internet overlay networks: Implications for architecture, industry structure and policy. In 33rd Research Conference on Communication, Information and Internet Policy, Arlington, Virginia.
Coley, C. D., & Wesinger Jr, R. E. (2000). U.S. Patent No. 6,061,798. Washington, DC: U.S. Patent and Trademark Office.
