Cisco Certified Network Professional 2025 – 400 Free Practice Questions to Pass the Exam

The primary function of IPv6-over-IPv4 tunnels is to create an IPv6 tunnel over an IPv4 network. This tunneling allows IPv6 packets to be encapsulated within IPv4 packets, enabling the transmission of IPv6 traffic over an existing IPv4 infrastructure. This is particularly important during the transition period where networks are shifting from IPv4 to IPv6. It allows IPv6-only devices to communicate across IPv4 networks, facilitating gradual adoption of IPv6 without requiring immediate upgrades to all network equipment.

This tunnel encapsulation process ensures that IPv6 packets can be sent and received over a network that does not natively support IPv6. It addresses the need for compatibility in mixed environments, allowing for a smoother transition while maintaining connectivity.

By contrast, routing IPv4 traffic over IPv6, securing IPv4 traffic, and facilitating NAT64 translation do not accurately describe the purpose of creating an IPv6 tunnel within an IPv4 network. These concepts involve different network functions and implementations unrelated to the specific task of tunneling IPv6 traffic over an IPv4 infrastructure.