Advanced Placement (AP) Computer Science

What is a major limitation of IPv4?

1. It cannot support enough devices for the global population

2. It is not compatible with modern networking

3. It does not provide security features

4. It can only connect to a few devices

The correct answer is: It cannot support enough devices for the global population

A major limitation of IPv4 is its inability to support the growing number of devices connected to the internet. IPv4 uses a 32-bit address scheme, which allows for approximately 4.3 billion unique IP addresses. This number seemed sufficient in the early days of the internet, but with the exponential growth of the internet, mobile devices, and the emergence of the Internet of Things (IoT), the available IPv4 addresses have been exhausted in many regions. This limitation presents significant challenges for ensuring connectivity for all devices globally as more people come online and more devices require internet access. The shift to IPv6, which offers a much larger address space, has been necessary to accommodate the increasing demand for IP addresses. While issues such as security features and compatibility with modern networking may arise, they are not the primary limitation attributed to IPv4. Security can be added through various protocols, and although IPv4 is older, it is still widely used and compatible with many modern networking technologies despite these concerns. The specific limitation in question is primarily about the quantity of addresses available through the IPv4 system.