Briefly describe overlapping.

Question

What will be an ideal response?

Answer 1

Overlapping occurs when the internal network has been incorrectly configured for an IP range that actually exists on the Internet (registered to another entity) or when two companies merge and each company was using the same private IP address range. This problem usually occurs only when uninformed network engineers configure a network using arbitrary addresses. Sometimes the thought is that a connection to the Internet will never be required. In this case, the organization cannot connect directly to the Internet because it has an IP range registered to someone else. This overlapping problem can be solved using NAT because NAT hides the incorrectly configured internal IP scheme. The NAT router must be configured to translate the internal IP addresses to a valid external address or address range. This is really no different than previous forms of NAT except that the organization's internal IP address range actually belongs to someone else. The "someone else" just does not know about it because those addresses are never exposed to the Internet, thanks to NAT. Most companies do not run into this problem because their network engineers and designers know to use one of the private IP address ranges (10.x.x.x, 172.16.x.x-172.31.x.x, and 192.168.x.x.) when configuring a private internal TCP/IP network.