How many devices can IPv4 support?

IPv4 can support a maximum of 4,294,967,296 devices.

This number is derived from the structure of an IPv4 address, which is a 32-bit number. Because each bit can be either a 0 or a 1, the total number of unique combinations is 2 raised to the power of 32, or 2³². According to the reference, a 32-bit IPv4 address is large enough to support 2³² computers.

Here's a breakdown for clarity:

• IPv4 Address Structure: IPv4 addresses are 32-bit numbers.
• Binary Representation: Each bit can be 0 or 1, making it a binary system.
• Calculation: The total number of possible addresses is calculated as 2³², which equals 4,294,967,296.

Therefore, the theoretical limit of unique devices that can be directly addressed using IPv4 is 4,294,967,296. It's important to note that not all of these addresses are available for general use, as some are reserved for specific purposes.