IPv6 Transition Poses New Security Threats The countdown to the saturation of the IPv4 address supply is now down to a matter of months: and along with the vast address space of the next-generation IPv6 architecture comes more built-in network security as well as some new potential security threats. IPv6 has been in the works for over a decade now, but with the exhaustion of the IPv4 address space expected anywhere from spring to June of 2011, the long transition to the new IP may finally be on the radar screen for some organizations.