6to4 provides IPv6 connectivity over IPv4 networks without explicit tunnels.

6to4 provides IPv6 connectivity over IPv4 networks without explicit tunnels.

• A. Teredo
• B. Dual Stack
• C. NAT64
• D. 6to4

Answer: (D)

The concept being tested is automatic tunneling of IPv6 over an IPv4 network without manual tunnel setup. 6to4 does this by using the IPv4 address of a device to form a 2002::/16 IPv6 prefix. When IPv6 traffic is sent, it’s encapsulated inside IPv4 packets (protocol 41) and travels across the IPv4 network to a 6to4 relay, which then forwards it as native IPv6. This lets a site have IPv6 connectivity without configuring a separate tunnel endpoint. Teredo, while also designed to carry IPv6 over IPv4, focuses on IPv4 NAT traversal using UDP and specific tunneling mechanics, not the automatic 6to4 prefix-based approach. Dual Stack means running both IPv4 and IPv6 on devices or networks without relying on a tunnel to carry IPv6 over IPv4. NAT64 translates between IPv6 and IPv4 to let IPv6-only clients reach IPv4 servers, rather than encapsulating IPv6 in IPv4 for transmission.

The concept being tested is automatic tunneling of IPv6 over an IPv4 network without manual tunnel setup. 6to4 does this by using the IPv4 address of a device to form a 2002::/16 IPv6 prefix. When IPv6 traffic is sent, it’s encapsulated inside IPv4 packets (protocol 41) and travels across the IPv4 network to a 6to4 relay, which then forwards it as native IPv6. This lets a site have IPv6 connectivity without configuring a separate tunnel endpoint.

Teredo, while also designed to carry IPv6 over IPv4, focuses on IPv4 NAT traversal using UDP and specific tunneling mechanics, not the automatic 6to4 prefix-based approach. Dual Stack means running both IPv4 and IPv6 on devices or networks without relying on a tunnel to carry IPv6 over IPv4. NAT64 translates between IPv6 and IPv4 to let IPv6-only clients reach IPv4 servers, rather than encapsulating IPv6 in IPv4 for transmission.