Static NAT Versus Dynamic NAT
Static NAT employs a 1:1 mapping technique between internal and external IP addresses. This mapping technique is often utilized when devices within the local or internal network are supposed to access the internet (Forouzan & Fegan, 2007). Dynamic NAT, unlike static NAT, is used to map a cluster of addresses within the internal network to one or more external addresses called address pool. The table below presents the differences between static and dynamic NAT.
|Uses 1 to 1 mapping approach for local and global addresses.||Uses a ratio of many to a few mapping approaches; that is, the number of local addresses mapped are more than the number of global addresses.|
|Maps distinctive local/internal IP address to distinctive global/external IP address.||Maps many distinctive local/internal IP addresses to a pool of global/external IP address.|
|The number of users with ability to access external resources is not limited because of the 1:1 mapping approach which ensures a user has a unique internal and external IP.||The number of users who can access external resources are limited to the number of global addresses in the address pool. Once all the addresses in the pool are used, other users cannot be connected to the external network.|
|Because of the static (not changing) IP addresses, this approach is less secure as hosts remain with same IP addresses which makes mapping easier for hackers.||More secure because of the ever-changing hosts’ IP addresses which makes it difficult for hackers to map (White, 2016).|
Forouzan, B. A., & Fegan, S. C. (2007). Data communications and networking. 4th ed. New York: McGraw-Hill Higher Education, pp.563-564.
White, C. M. (2016). Data communications & computer networks: a business users approach. 8th ed. Boston, MA: Cengage Learning., pp.362.