unicast
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... relay routers. Effectively it treats the wide area IPv4 network
as a unicast point-to-point link layer. The mechanism is intended as
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... 6OVER4]) the 6to4 mechanism must assume
only unicast capability in its underlying IPv4 carrier network. An
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... destination address
embeds a V4ADDR which is not in the format of a global unicast
address MUST be silently discarded by both encapsulators and
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... Hinden., R, O'Dell, M. and S. Deering, "An IPv6 Aggregatable Global Unicast Address Format", RFC 2374hist(-> 3587), July 1998. ...