Which version of Internet Protocol is widely used today?

• A. IPv5
• B. IPv4
• C. IPv6
• D. IPv3

Answer: (B)

The widely used version of Internet Protocol today is IPv4. This protocol has been foundational for internet communication since it was introduced in the early 1980s. IPv4 addresses are 32 bits long, allowing for approximately 4.3 billion unique IP addresses, which were initially more than sufficient for the number of devices connected to the internet.

However, the rapid growth of internet-connected devices has led to the exhaustion of these addresses, prompting the transition to IPv6. While IPv6, which uses 128-bit addresses, is becoming more prevalent and is designed to accommodate the expanding number of devices, IPv4 remains the most commonly implemented protocol as of the latest data. Even with ongoing efforts to encourage adoption of IPv6, many systems and networks still rely on IPv4 for their operations, making it the current standard.

Understanding IPv4's role is crucial for anyone involved in IT, as it is still the backbone of internet connectivity and the protocol many computer and networking professionals encounter daily.