Vint Cerf on the Origins of 32-bit IP Addressing

Via a weekly wrap-up post by Dion Almaer on the Google Code Blog comes mention of a Google Tech Talk video from their IPv6 Conference 2008. It is a panel discussion called “What will the IPv6 Internet look like?” and it offers insight into the difficulties of transitioning to the next generation IP transport protocol. Although it has been years since I’ve seen the business end of managing an actual IP network, I found the discussion a fascinating look at the issues that are ahead of network engineers and device manufacturers around the world.

The part that caught my ears, though, was an exchange between Vint Cerf, vice president and chief internet evangelist at Google, and Bob Hinden, chief internet technologist at Nokia Networks. It starts at 13 minutes and one second into the video with Vint as moderator of the panel addressing a question from the audience about whether the panelists are proud of the work done on IPv6.

Vint Cerf
Well, just speaking for myself — like I said earlier this morning — I believe that v6 is the only thing that we can do right now to make sure that address space is available and that we preserve as much as possible the end to end structure of the network.
Bob Hinden
Can I get one other comment in here? You reminded me of something. So back when Vint and everyone was starting the v4 — the current internet — was not a sure thing. Back, you know, 15, 20 years ago. And there were lots of –
Vint Cerf
I’m sorry, it’s 30 years ago because the decision — [laughter]. No, I’m serious, the decision to put a 32-bit address space on there was the result of a year’s battle among a bunch of engineers who couldn’t make up their minds about 32, 128 or variable length. And after a year of fighting I said — I’m now at ARPA, I’m running the program, I’m paying for this stuff and using American tax dollars — and I wanted some progress because we didn’t know if this is going to work. So I said 32 bits, it is enough for an experiment, it is 4.3 billion terminations — even the defense department doesn’t need 4.3 billion of anything and it couldn’t afford to buy 4.3 billion edge devices to do a test anyway. So at the time I thought we were doing a experiment to prove the technology and that if it worked we’d have an opportunity to do a production version of it. Well — [laughter] — it just escaped! — it got out and people started to use it and then it became a commercial thing. So, this [IPv6] is the production attempt at making the network scalable. Only 30 years later.