> A much better solution here would have been an incredibly conservative change to ipv4 to expand the number of available address space

"And what do you base this belief on?

Fact is you'd run into exactly the same problems as with IPv6. Sure, network-enabled software might be easier to rewrite to support 40-bit IPv4+, but any hardware-accelerated products (routers, switches, network cards, etc.) would still need replacement (just as with IPv6), and you'd still need everyone to be assigned unique IPv4+ addresses in order to communicate with each other (just as with IPv6)."[0]

0: https://news.ycombinator.com/item?id=37120422

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avidiax an hour ago | parent | next [-]

> Fact is you'd run into exactly the same problems as with IPv6.

If you treat IPv4 addresses as a routable prefix (same as today), then the internet core routers don't change at all.

Only the edge equipment would need to be IPv4+ aware. And even that awareness could be quite gradual, since you would have NAT to fall back on when receiving an IPv4 classic packet at the network. It can even be customer deployed. Add an IPv4+ box on the network, assign it the DMZ address, and have it hand out public IPV4+ addresses and NAT them to the local IPv4 private subnet.

IPv6 seems to be a standard that suffered from re-design by committee. Lots of good ideas were incorporated, but it resulted in a stack that had only complicated backwards compatibility. It has taken the scale of mobile carriers to finally make IPv6 more appealing in some cases than IPv4+NAT, but I think we are still a long way from any ISP being able to disable IPv4 support.

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throw0101a 5 minutes ago | parent | next [-]

> Only the edge equipment would need to be IPv4+ aware.

"Only"? That's still the networking stack of every desktop, laptop, phone, printer, room presentation device, IoT thing-y. Also every firewall device. Then recompile every application to use the new data structures with more bits for addresses.

And let's not forget you have to update all the DNS code because A records are hardcoded to 32-bits, so you need a new record type, and a mechanism to deal with getting both long and short addresses in the reply (e.g., Happy Eyeballs). Then how do you deal with a service that only has a "IPv4+" address but application code that is only IPv4-plain?

Basically all the code and infrastructure that needed to be updated and deployed for IPv6 would have to be done for IPv4+.

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p_l 29 minutes ago | parent | prev | next [-]

No, routers would have to be fixed anyway, because even if you put extra bits into extension header we have 30 years of experience that routers and ISPs will regularly fuck around with those extra bits - it's related to why we have TLS GREASE option.

Application rework would be exactly the same as with v6, because the issue was not with v6 but with BSD Sockets API exposing low-level details to userland.

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sgjohnson 39 minutes ago | parent | prev [-]

> Only the edge equipment would need to be IPv4+ aware. And even that awareness could be quite gradual, since you would have NAT to fall back on when receiving an IPv4 classic packet at the network. It can even be customer deployed. Add an IPv4+ box on the network, assign it the DMZ address, and have it hand out public IPV4+ addresses and NAT them to the local IPv4 private subnet.

Congratulations, you’ve re-invented CGNAT, with none of the benefits, and the additional hassle of it being an entirely new protocol!

No. No “extra bits” on an IPv4 address would have ever worked. NAT itself is a bug. Suggesting that as an intentional design is disingenuous.

	▲	avidiax 20 minutes ago \| parent [-]
		I have not "reinvented CGNAT". It is hierarchal public addressing similar to IPv4 and IPv6. The edge router has an IPv4+ subnet (either a classic v4 address, or part of a v4+ address). It maintains an L2 routing table with ARP+, and routes IPv4+ packets to the endpoint without translation. Private subnetting and NAT is only needed to support legacy IPv4 clients. CGNAT pools IPv4 public addresses and has an expanded key for each connection, and translates either 4 to 6 or into a private IPv4 subnet. My proposal needs no pooling and only requires translation if the remote host is IPv4 classic and the edge router is not assigned a full IPv4+/24.

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redox99 2 hours ago | parent | prev [-]

Hardware would catch up. And IPv4 would never go away. If you connect to 1.1.1.1 it would still be good ole IPv4. You would only have in addition the option to connect to 1.1.1.1.1.1.1.2 if the entire chain supports it. And if not, it could still be worked around through software with proxies and NAT.

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hypeatei 2 hours ago | parent [-]

So... just a less ambitious IPv6 that would still require dual-stack networking setups? The current adoption woes would've happened regardless, unless someone comes up with a genius idea that doesn't require any configuration/code changes.

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krupan an hour ago | parent | next [-]

I disagree. The current adoption woes are exactly because IPv6 is so different from IPv4. Everyone who tries it out learns the hard way that most of what they know from IPv4 doesn't apply. A less ambitious IPv4 is exactly what we need in order to make any progress

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throw0101a 3 minutes ago | parent | next [-]

> I disagree. The current adoption woes are exactly because IPv6 is so different from IPv4.

How is IPv6 "so different" than IPv4 when looking at Layer 3 and above?

(Certainly ARP vs ND is different.)

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bc569a80a344f9c 32 minutes ago | parent | prev | next [-]

It’s not _that_ different. Larger address space, more emphasis on multicast for some basic functions. If you understand those functions in IPv4, learning IPv6 is very straightforward. There’s some footguns once you get to enterprise scale deployments but that’s just as true of IPv4.

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sgjohnson 35 minutes ago | parent | prev [-]

But that is a bug in history. IPv6 was standardized BEFORE NAT.

“most what they know from IPv6” is just NAT.

> A less ambitious IPv4 is exactly what we need in order to make any progress

but we’re already making very good progress with IPv6? Global traffic to Google is >50% IPv6 already.

	▲	btilly a few seconds ago \| parent [-]
		Current statistics are that a bit over 70% of websites are IPv4 only. A bit under 30% allow IPv6. IPv6 only websites are a rounding error. Therefore if I'm on an IPv6 phone, odds are very good that my traffic winds up going over IPv4 internet at some point. We're 30 years into the transition. We are still decades away from it being viable for servers to run IPv6 first. You pretty much have to do IPv4 on a server. IPv6 is an afterthought.

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hackthemack an hour ago | parent | prev | next [-]

Sort of. I think people would understand

201.20.188.24.6

And most of what they know about how it works clicks in their mind. It just has an extra octet.

I also think hardware would have been upgraded faster.

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redox99 35 minutes ago | parent | prev [-]

The main thing is keeping current addresses, not having both an ipv4 and ipv6 address.

Just like for an apartment you append something like 5B. And for a house you don't need that.