Currently, IP version $4$ address space is depleted due to the manufacture, adoption and hence proliferation of IP addressable device such IP telephone, wireless PDAs, mobile$/$cell phones, game consoles, and home networking systems. Techniques, such as NAT$/$PAT$,$ DHCP and CIDR have been implemented to prolong the life of IPv$4.$ These techniques reuse the existing IPv$4$ address space and handle the address space allocation more efficiently. However, a lasting solution is to migrate to IPv$6.$ Many devices and applications already support IPv$6.$

$1.$ In one sentence, state how can you support or propagate the implementation of IPv$6$ addressing?

$2.$ Will IPv$4$ networks continue, or will IPv$6$ eventually take over? How long will it take? Justify your response with appropriate and up$-$to$-$date technical details using only two sentences.

$3.$ Use three sentences to explain the aggregation of IPv$6$ addresses in terms of nibbles $(4$ bits$)$ rather than in bits.

$4.$ Explain how NAT and PAT have prolonged IPv$4$ implementation.