IPv4 was introduced in 1983 and now forms the basis for internet routing. It is a 32-bit addressing system so there are 2^32 or 4,294,967,296 addresses (some addresses are reserved so the usable number is slightly less). The internet is running out of IPv4 addresses. IPv6 was drafted in 1998 and finally standardized in 2017. IPv6's address space is extended to 2^128 or 3.4 x 10^38. The internet is currently transitioning over to IPv6.
IPv6 traffic now accounts for over 30% of Google's user traffic. Akamai lists IPv6 traffic at 17.79%.
When will global IPv4 traffic account for less than 1% of total internet traffic?
This question will resolve on the date when it is estimated that less than 1% of global internet traffic uses IPv4, by ratio of IPv4 transactions to total transactions (not bandwidth or other metrics). This question will resolve according to data from Akamai, or if they no longer publish this data, Metaculus Admins may choose another major content delivery network as the source at their discretion.