Question: which one of these are a valid ipv4 address?
Answer: IPV4, the traditional numbering scheme, uses four integers ranging from zero to 255 and set apart by periods. For example, "204.120. 0.15" is a valid IPV4 address. A newer IPV6 scheme, designed to eventually replace IPV4, uses a larger, more complex set of numbers mixed with other characters, such as letters.