The ISP Column
A column on things Internet Other Formats:
IP Addresses through 2025
January 2026
Geoff Huston
It's time for another annual roundup from the world of IP addresses. Let’s see what has changed in the past 12 months in addressing the Internet and look at how IP address allocation information can inform us of the changing nature of the network itself.
Back around 1992, the IETF gazed into their crystal ball and tried to understand how the Internet was going to evolve and what demands that would place on the addressing system as part of the “IP Next Generation” study. The staggeringly large numbers of connected devices that we see today were certainly within the range predicted by that study. The assumption made at the time was that we would continue to use much the same IP protocol architecture, including the requirement that each connected device was assigned a unique IP address, and the implication was that the 32-bit address field defined in version 4 of the IP protocol was clearly going to be inadequate to cope with the predicted number of connected devices. A span of 4 billion address values was just not large enough.
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