Which statement about private IP addresses is true?

Which statement about private IP addresses is true?

• A. Private IP addresses cannot be routed over the Internet
• B. Private IP addresses are globally unique
• C. Private IP addresses are assigned by the DNS
• D. Private IP addresses are publicly routable

Answer: (A)

Private IP addresses are reserved ranges that stay inside local networks and are not meant to be reachable on the public Internet. Internet routers don’t forward packets that use these private ranges as source or destination, which is why devices on a private network can’t be reached directly from outside without some translation or tunneling. In practice, networks use NAT to talk to the Internet: the private address is translated to a single public IP on outbound traffic, so many private devices can share one public address. This is why the statement about private addresses not being routable over the Internet is true. The other ideas don’t fit: private addresses aren’t globally unique and can be reused in different networks; DNS doesn’t assign addresses—the devices or DHCP assign private addresses within a private network; and private addresses aren’t publicly routable, meaning they aren’t designed to be reachable across the public Internet.

Private IP addresses are reserved ranges that stay inside local networks and are not meant to be reachable on the public Internet. Internet routers don’t forward packets that use these private ranges as source or destination, which is why devices on a private network can’t be reached directly from outside without some translation or tunneling. In practice, networks use NAT to talk to the Internet: the private address is translated to a single public IP on outbound traffic, so many private devices can share one public address.

This is why the statement about private addresses not being routable over the Internet is true. The other ideas don’t fit: private addresses aren’t globally unique and can be reused in different networks; DNS doesn’t assign addresses—the devices or DHCP assign private addresses within a private network; and private addresses aren’t publicly routable, meaning they aren’t designed to be reachable across the public Internet.