IPv4 vs IPv6 Headers

What this networking fundamentals question tests

This is an easy conceptual question on packet structure that often appears in interviews for infrastructure, systems, and network-focused roles. It assesses whether you understand the practical differences between the two most widely deployed IP versions, and why IPv6 was redesigned the way it was.

Candidates are expected to identify and explain the key structural and functional changes—such as header length, addressing scheme, optional fields, and how they affect processing efficiency. Rather than memorizing byte-level details, the question rewards clarity on why each change matters in real networks.

• Header field organization and size
• Address representation and namespace
• Handling of options and extensibility
• Impact on routing and packet processing