IPv6 "Dynamic" and Automatic 6to4

Reading the How To Master CCNP Route book, I came across static and dynamic IPv6 tunnels for IPv6 migration. I keep getting caught up on the statement (page 318):

Dynamic multipoint IPv6 tunnels are another migration technique we can use. It’s called
dynamic because we don’t have to specify the end-point IPv4 address ourselves but its
being automatically determined.

However, after successfully configuring the topology and being able to ping the loopbacks…I am still left wondering how the “end-point IPv4 address is automatically determined”.

How are the end-point IPv4 address automatically determined? By the two static routes we configure? I understand that the keyword 6to4 enables the 2002::/16 prefix and then it uses the IPv4 address on the interface being used to create the tunnel, and converts it to HEX and then adds it to the 2002::/16 prefix. But that isn’t the destination IPv4 address…its the local IPv4 address…so I am not sure how the end-points are “automatically determined”.

Please advise.

A post was merged into an existing topic: How to configure IPv6 Automatic 6to4 Tunneling