Final answer:
The major difference between IPv4 and IPv6 is that IPv6 has a much larger address space compared to IPv4, enabling the allocation of significantly more unique addresses.
Step-by-step explanation:
The major difference between IPv4 and IPv6 is that IPv6 has a much larger address space compared to IPv4. While IPv4 uses 32-bit addresses, allowing for about 4.3 billion unique addresses, IPv6 uses 128-bit addresses, which enables the allocation of approximately 340 undecillion unique addresses.
In addition to the larger address space, IPv6 also introduces improvements in terms of addressing, security, and network management. It supports more types of data, allowing for better support for multimedia and real-time communication.
It's important to note that IPv6 does not use domain names directly. Instead, it still relies on numeric addresses, but with an expanded address space to accommodate future internet growth.