Which of the following is NOT a feature of IPv6?

The correct answer is that limited address assignments is not a feature of IPv6. In fact, one of the primary improvements introduced by IPv6 is its significantly increased address space compared to IPv4. This expanded address space means that IPv6 can support a virtually unlimited number of unique IP addresses, allowing for far more devices to be connected to the internet without the limitations imposed by the address scarcity seen in IPv4.

IPv6 was designed to accommodate the growing number of devices and services requiring unique addresses, eliminating issues related to address exhaustion. Therefore, contrary to the characteristic of limited address assignments, IPv6 offers a vast pool of addresses, significantly enhancing the ability for devices to obtain their own unique identifiers on the network.

In addition, IPv6 simplifies the packet header structure, improving routing and processing efficiency. It also integrates improved security features, including mandatory support for IPsec, which enhances data integrity and privacy. These features collectively highlight that limited address assignments is not a characteristic of IPv6, reinforcing the technology's purpose of addressing the limitations faced in previous versions.