What is a major advantage of IPv6 over IPv4?

• A. Faster routing across all networks.
• B. Uses NAT by default.
• C. Larger address space.
• D. Requires less memory.

Answer: (C)

A much larger address space is the standout advantage. IPv4 uses 32-bit addresses, which limits the total to about 4.3 billion unique addresses—insufficient for the growth of devices, services, and IoT. IPv6 uses 128-bit addresses, offering roughly 3.4 x 10^38 unique addresses, which allows every device to have a globally unique address and supports scalable, hierarchical routing. This abundance also reduces the pressure to use techniques like NAT for address conservation, though NAT isn’t built into IPv6 by default. The idea that routing would be faster across all networks isn’t guaranteed, and memory usage isn’t reduced because IPv6 carries larger addresses and headers.