Which of the following statements represent characteristics of an automatic 6to4 tunnel through an IPv4 network? (Choose all that apply.)
A. There is a NAT-PT router on either end of the tunnel.
B. There is a dual stack router on either end of the tunnel.
C. Each 6to4 site will have a /48 prefix.
D. Each 6to4 site will have a /16 prefix.
E. The IPv4 addresses of the edge routers are part of the site prefix.
F. The IPv6 addresses of the sending and receiving IPv6 hosts are part of the site prefix.
Explanation:
When implementing an automatic 6to4 tunnel, each IPv6 site receives a 48-bit prefix. The hexadecimal equivalent of the IPv4 address of the edge router is appended to 0x2002 and followed with the prefix to identify each end of the tunnel.
Each end of the tunnel must be a dual stack router, which is one that can route both IPv4 and IPv6 traffic. For example, if the edge router’s IPv4 address were 192.168.99.1, the hexadecimal equivalent of the address (c0a8:6301) would be inserted between 0X2002 and the /48 prefix, resulting in a packet with the IPv6 address 2002:c0a8:6301::/48 to arrive at the tunnel endpoint address.
A Network Address Translation – Port Translation (NAT-PT) router performs translation from IPv4 to IPv6. It is not used in a 6to4 tunnel.
Each site does not have a /16 prefix with a 6to4 tunnel. Rather, each site has a /48 prefix.
The IPv6 address of each IPv6 host is not part of the site prefix. These addresses are retained within the IPv6 portion of the header, and will be read after the frame reaches the end of the tunnel for eventual IPv6 routing on the far end.
Objective:
Network Principles
Sub-Objective:
Recognize proposed changes to the network