In the field of IPv6 deployment, IPv6 brokenness was bad behavior seen in early tunneled or dual stack IPv6 deployments where unreliable or bogus IPv6 connectivity is chosen in preference to working IPv4 connectivity. This often resulted in long delays in web page loading, where the user had to wait for each attempted IPv6 connection to time out before the IPv4 connection was tried.[1] These timeouts ranged from being near-instantaneous in the best cases, to taking anywhere between four seconds to three minutes.[2]
IPv6 brokenness is now generally regarded as a solved problem for almost all practical purposes, following improvements at both the transport and application layers.[3]
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