It all works pretty well if the client have IPv4 and IPv6
_AND_ both works. But to some degree the functionality and
user experience goes down if either of IPv4 or IPv6 have
Same is true for a host with two IPv4 addresses and either of
the IPv4 addresses have problems.
Same is true for a host with two IPv6 addresses and either of
the IPv6 addresses have problems.
The problem can be solved by carefully designing connection
establishment protocols to support multiple addresses of a
host, which means no solution exists at the connectionless
layer of IP.
Modified TCP, which send multiple SYN to several addresses
of a peer helps a lot to reduce timeout.
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