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A Bad Idea if Taken Literally Section 2.2 “After it has selected a Link-Local IPv4 address, a host MUST test to see if the Link-Local IPv4 address is already in use before beginning to use it. When a network interface transitions from an inactive to an active state, the host does not have knowledge of what Link-Local IPv4 addresses may currently be in use on that link, since the network interface may have been inactive when a conflicting address was claimed.” Implications Host connects to an adhoc POA, selects IPv4LL address Host moves to another (configured) POA Performs IPv4LL claim and defend Uses selected IPv4LL address Host never obtains a routable address! Solution Don’t “select” an IPv4LL as a first resort OR Test reachability of autoconf neighbor(s) first |