0.0.0.0/0 refers to which set of addresses?

• A. All addresses
• B. Local network only
• C. Broadcast addresses
• D. Private addresses

Answer: (A)

In IPv4 CIDR notation, 0.0.0.0/0 represents every possible address. The /0 means zero bits are fixed, so any 32‑bit value matches this prefix. This is why it’s used as the default route in routing tables: if there’s no more specific route for a destination, packets are sent via this default path. It isn’t limited to the local network, it isn’t specifically a broadcast address, and it isn’t restricted to private address ranges. Private ranges and broadcasts are defined with their own particular prefixes, like 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, or 255.255.255.255 for limited broadcasts. So 0.0.0.0/0 covers all addresses.