What is a key difference between IPv4 and IPv6?

The choice indicating that IPv4 can support fewer devices than IPv6 is indeed correct because of the fundamental differences in address space. IPv4 uses 32-bit addresses, allowing for approximately 4.3 billion unique IP addresses. In contrast, IPv6 employs 128-bit addresses, which exponentially increases the number of possible addresses to about 340 undecillion (that's 340 followed by 36 zeros). This vast address space of IPv6 was designed specifically to accommodate the ever-growing number of internet-connected devices.

The expansion to IPv6 is essential not only for providing unique addresses to every device but also for enabling the Internet of Things (IoT) and the future of online connectivity. As the digital landscape continues to evolve, the limitations of IPv4 become more apparent, emphasizing the need for a protocol that can handle a significantly larger number of devices.