Three decades after RFC 1883 promised to future-proof the internet by expanding the available pool of IP addresses from around 4.3 billion to over 340 undecillion, IPv6 has yet to achieve the dominance its creators envisioned. Data from Google, APNIC and Cloudflare analyzed by The Register shows less than half of all internet users rely on IPv6 today. "IPv6 was an extremely conservative protocol that changed as little as possible," APNIC chief scientist Geoff Huston told The Register. "It was a classic case of mis-design by committee." The protocol's lack of backward compatibility with IPv4 meant users had to choose one or run both in parallel. Network address translation, which allows thousands of devices to share a single public IPv4 address, gave operators an easier path forward. Huston adds: "These days the Domain Name Service (DNS) is the service selector, not the IP address," Huston told The Register. "The entire security framework of today's Internet is name based and the world of authentication and channel encryption is based on service names, not IP addresses." "So folk use IPv6 these days based on cost: If the cost of obtaining more IPv4 addresses to fuel bigger NATs is too high, then they deploy IPv6. Not because it's better, but if they are confident that they can work around IPv6's weaknesses then in a largely name based world there is no real issue in using one addressing protocol or another as the transport underlay." But calling IPv6 a failure misses the point. "IPv4's continued viability is largely because IPv6 absorbed that growth pressure elsewhere -- particularly in mobile, broadband, and cloud environments," said John Curran, president and CEO of the American Registry for Internet Numbers. "In that sense, IPv6 succeeded where it was needed most." Huawei has sought 2.56 decillion IPv6 addresses and Starlink appears to have acquired 150 sextillion. Read more of this story at Slashdot.