The Reg does 240/4

Tue Feb 13 07:18:12 UTC 2024

----- Original Message -----
> From: "Dave Taht" <dave.taht at gmail.com>

> The angst around ipv6 on hackernews that this triggered was pretty
> revealing and worth thinking about independently.
> https://news.ycombinator.com/item?id=39316266

Thanks; the source where I got the other link mentioned that, and I meant
to include it...

> I was inspired to try a couple traceroutes. It used to be 240 escaped
> my prior comcast router and wandered around a while; it does not do
> that anymore. I would be dryly amused if that box was actually running
> my old OpenWrt bcp38 stuff which blocked 240 for a couple years. My
> cloud works, my aws stack works, openwrt works.

Damn; I haven't touched the bcp38 wiki in some time.  Thanks for the reminder.

> Peering into a murky crystal ball, say, 5 years in the future:
> 
> Another thing that I worry about is port space exhaustion, which is
> increasingly a thing on firewalls and CGNs. If I can distract you - in
> this blog cloudflare attempted to cut the number of ipv4 addresses
> they use from 2 to 1, after observing some major retry issues. With a
> nice patch, reducing the problem.
> 
> https://blog.cloudflare.com/linux-transport-protocol-port-selection-performance/

Interesting.  Isn't that something CGNAT implementers would have had to deal with
already?

> Peering further into the soi-distant decades ahead, perhaps we should
> just allocate all the remaining protocol space in the IP header to a
> quic native protocol, and start retiring the old ones.

Well, I've been able to avoid thinking about it for some time, but ISTR my 
reaction to QUIC as violating a number of organized religions' blasphemy 
rules...

> /me hides

Indeed.

Cheers,
-- jra
-- 
Jay R. Ashworth                  Baylink                       jra at baylink.com
Designer                     The Things I Think                       RFC 2100
Ashworth & Associates       http://www.bcp38.info          2000 Land Rover DII
St Petersburg FL USA      BCP38: Ask For It By Name!           +1 727 647 1274