Which migration technique encapsulates IPv6 packets inside IPv4 packets for transport over IPv4 networks?

The correct answer is tunneling. Tunneling is a technique used to encapsulate packets from one protocol inside packets of another protocol. In this context, tunneling specifically refers to encapsulating IPv6 packets within IPv4 packets to facilitate their transit over an IPv4 network infrastructure. This method is essential for transitioning from IPv4 to IPv6, allowing IPv6 traffic to be transmitted across existing IPv4 networks, which may not natively support IPv6.

The encapsulation process involves wrapping the IPv6 packet in an IPv4 packet so that it can traverse the IPv4 network. Once it reaches its destination, the IPv4 header is stripped off, and the original IPv6 packet is extracted and processed. This technique is particularly useful during the migration phase, where both IPv4 and IPv6 protocols need to coexist.

Other techniques such as bridging, routing, and switching serve different purposes. Bridging involves connecting multiple network segments at the data link layer without altering the packets, while routing focuses on directing packets through a network based on their destination IP addresses at the network layer. Switching operates at the data link layer, efficiently forwarding frames within the same local area network without encapsulating or altering the original packets, making them unsuitable for the specific purpose of encapsulating