What is a common characteristic of a private network?

• A. It uses private IP address space
• B. It uses public IP addresses
• C. It has no security
• D. It uses only IPv6

Answer: (A)

Private networks rely on private IP address space to identify devices inside the organization without using addresses that are unique on the global Internet. These private ranges (for IPv4, 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) aren’t routable on the public Internet, so internal devices can communicate using these addresses while external access typically goes through a router with NAT. That use of non-routable addresses conserves public IPv4 space and provides a layer of isolation, since directly reachable devices on the Internet aren’t exposed by default. The other options don’t define private networks: public IPs are generally not used inside a private network, security isn’t guaranteed simply by being private, and private networks can use IPv6 as well (including IPv6 private addressing).