The document discusses Marco d'Itri's thoughts on the transition to IPv6. It describes the transition as ongoing, with no flag days, as IPv6 adoption grows. It notes that while IPv4 NAT is easy for access networks, it is difficult for servers. Many large content providers already use IPv6. The transition involves steps before IPv4 addresses ran out, the current transition period, and after the transition when IPv4 will be optional. IPv6 adoption is growing in several countries like Belgium and the US. Eventually IPv4-only islands will need to make themselves accessible over IPv6. The document provides advice on starting an IPv6 transition and offers a simple IPv6 addressing plan.