Mike Meyers’ CompTIA Network+ Certification Passport, 4th Edition (Exam N10-005), 4th Edition

Private vs Public IP Addresses

Lots of folks use TCP/IP in networks that either aren’t connected to the Internet or want to hide their computers from the rest of Internet. Certain groups of IP addresses, known as private IP addresses, are available to help in these situations. All routers destroy private IP addresses. Those addresses can never be used on the Internet, making them a handy way to hide systems. Anyone can use these private IP addresses, but they’re useless for systems that need to access the Internet—unless you use the mysterious and powerful NAT, which I’ll discuss in the next chapter. (Bet you’re dying to learn about NAT now!) For the moment, however, let’s just look at the ranges of addresses that are designated as private IP ...