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A comment on How Engineers at Digital Equipment Corp. Saved Ethernet. Parent comment

Re:How Engineers at Digital Equipment Corp. Saved Ethernet by rini17 on Monday April 08, 2024 @06:07PM (#39974239)
But this was what literally happened. All routers today support NAT and most of them actively use it. Isn't it a magical form of extended IPv4 address space? Could have been easily done in less band-aid fashion instead of chasing IPv6.
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Re:How Engineers at Digital Equipment Corp. Saved Ethernet by ianburrell on Monday April 08, 2024 @07:52PM (#39974915)
It is impossible to address hosts behind NAT. Only the public IPv4 address is visible.

It might have been possible to extend IPv4 by having each NAT hop add the internal IPv4 address as option header. Then it would be possible to refer to inside host directly with a list of addresses.

That isn't worth doing now because it would require rewriting everything to deal with the new protocol. For one thing, lots of NAT boxes remove all the option headers. The new protocol wouldn't be reliable.

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Re:How Engineers at Digital Equipment Corp. Saved Ethernet by inopinatus on Monday April 08, 2024 @10:23PM (#39975750)
Not a counterexample exactly, but your remark reminded me of this eldritch horror: https://blog.cloudflare.com/cloudflare-servers-dont-own-ips-...

TLDR: Cloudflare is using five bits from the port number as a subnetting & routing scheme, with optional content policy semantics, for hosts behind anycast addressing and inside their network boundary.

Filed in my bookmarks under "abominations".

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Re:How Engineers at Digital Equipment Corp. Saved Ethernet by jbernsteiniv on Tuesday April 09, 2024 @12:43AM (#39976239)
From the link: "A lot of Cloudflare's technology is well documented. For example, how we handle traffic between the eyeballs (clients) and our servers has been discussed"

Already 1 sentence in and we've already got Eldritchian horrors with customers described as just their watery orbs in their skull.

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Re:How Engineers at Digital Equipment Corp. Saved Ethernet by inopinatus on Monday April 08, 2024 @07:52PM (#39974913)
> Isn't it a magical form of extended IPv4 address space?

No.

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Re:How Engineers at Digital Equipment Corp. Saved Ethernet by vlovich123 on Monday April 08, 2024 @06:34PM (#39974426)
How?
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Re:How Engineers at Digital Equipment Corp. Saved Ethernet by djbusby on Monday April 08, 2024 @09:38PM (#39975531)
NAT doesn't change IP Header size, just the contents - while staying the same size. The header size is a requirement for compatibility.
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Re:How Engineers at Digital Equipment Corp. Saved Ethernet by adrianmonk on Tuesday April 09, 2024 @10:34AM (#39979884)
No, it's not a magical form of extended address space. It's a magical (clever) way of extending the networking without extending the address space.
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