IPv4 Octet Maximum Value Explained

An IPv4 address is structured into four parts, called octets or quads, separated by dots (e.g., 192.168.1.1). Each octet represents a sequence of 8 bits.

Understanding Binary Representation

In computing, a bit can hold one of two values: 0 or 1. An 8-bit sequence allows for $2^8$ unique combinations.

• Calculation: $2^8 = 2 \times 2 \times 2 \times 2 \times 2 \times 2 \times 2 \times 2 = 256$ possible combinations.

Determining the Maximum Value

These 256 combinations represent numerical values starting from 0. Therefore, the range of values for an 8-bit octet is from 0 to $2^8 - 1$.

• Maximum Value = $2^8 - 1$
• Maximum Value = $256 - 1$
• Maximum Value = 255

Thus, the maximum value that can be assigned to a single octet (quad) in an IPv4 address is 255.

Final Answer Check

Comparing this result with the given options:

• Option 1: 127 (Incorrect - This is the max value for a signed 8-bit integer, or the end of the loopback range)
• Option 2: 128 (Incorrect)
• Option 3: 255 (Correct)
• Option 4: 256 (Incorrect - This is the total number of values, not the maximum value)

The maximum value is 255.