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Comment by bushbaba | Hacker News Reader

I really wish we just did ipv4 on 64 but addresses. IPv6 is nearly a totally different paradigm, and has lead to adoption pain. Biggest being usability taking a back seat. People are being forced into using ipv6 not cause they want to, but from ip space exhaustion.

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I used to think that, until I actually started using IPv6. It's a much more well designed protocol. The way switches and routers announce prefixes and network information using well defined UDP multicast is elegant and more robust. You can use link-local IP to always connect to a device on a local network.

The biggest benefit for most users is having a large enough IP space that devices can self-assign a unique address with the networks prefix with very low risk of collision. Many of the problems seen on wifi or home networks are due to various ARP issues and devices not properly releasing their own DHCP addresses. It's still very common. I had a work laptop get booted off my network after 10 minutes for a while until eventually figuring out another device was stealing its assigned IP.

IPv4 today is a totally different paradigm than what IPv4 was in the 1980's and early 1990's.

IPng (IPv6) was designed when the original paradigm existed, not what we have now-a-days.

So, if we actually had been on track to do IPv6 in the decade it was defined, we could have gone a totally different way. Instead due to the rapid growth of the Internet in the mid 90's, IPv4 was morphed into something different and IPv6 had its own model until we started to need it again.

IPv6 itself isn't the right thing for mobile internet either; people expect their IP address to not change when they migrate towers, meaning the entire approach to routing doesn't work.

Isn't it like literally a data structure issue though? Like you have to route on prefixes? Like how else would you know where to go?

Ip routing is kind of like a tree (not a graph) in the ip regards, how would you get around it?

I admittedly don't know as much as I'd like about network, hence why I'm posing this question ;-)

If theres a way to efficiently model hierarchical domains for stuff like DNS/IP i'd love to know. Like, consistent hash rings maybe, but then we'd be reintroducing ring topologies...

Oh wait duh though. A cell tower is owned by a single company. Yeah that's prolly doable, the company can always buy beefier routers if they need the memory. And realistically speaking the virtual tree could be closely aligned to the physical one given how cell towers work.

The way it is done is to have an invisible layer underneath (mpls perhaps) that can do the routing.

However the correct ip way to do it would to have tcp(layer 4) decoupled from ip(layer 3) such that an ip address could change while maintaining the tcp stream. unfortunately this was not done, tcp has too many layer violations and is firmly interlocked with ip. I don't know much about the state of the art, does http over udp (quic) allow for ip address change?

Yes. Packets contain a connection identifier, so the connection can continue were it left off when the client switches ip.

In some ideal world IP values vary between 0 and 999 and you just add a new block if you run out of them, `999.999.999.999` would be the last standard IP, simply add another `.000` block and you get some more billions IPs.

Having letters in IPv6 feels wrong, at that point why not just have words, reinvent DNS at a lower level. You are already living on Cherry Picked Street, number 15, let your computer have the IP `cherry.picked.15.1`.

An IPv4 address on the wire is just a 32 Bit integer in big endian. The quad-dotted notation is the most common for IPv4 but you could also use hex or decimal. There was an article on HN just recently about that. I can't find it right now but try ping 0x7F000001 to get an idea. You don't even need a new protocol you could implement something like what three words or your 999.999.999 naming scheme locally and use it on the internet right now! No need to replace any routers or have anyone else upgrade.

It's the human method of interacting with that integer which is the problem.

Nobody is going to start saying IPv4 addresses as hex, people aren't used to base 16. "Just set your gateway to co.a8.0.fe" said nobody ever.

A 128-bit dotted quad would be equally unwieldy. Again "The IPv6 local range is 252.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000/7" said nobody ever.

Honestly 128 bits was too much. They should have just done 64 and stuck to dotted quad and ARP. That would probably have got more acceptance than what we have now.

64bits in hex would be reasonably compact, 1.5x the length of a MAC address.

Sure, we could even call those network subnets that way we've got plenty of space for all the internet and expansion since 32 wasn't enough, and have another 64 bits for host identifiers.

This feels familiar somehow...

So basically just "what three words" but for IP. Just don't let a VC backed company own the address space and then encourage public/government organisation to adopt it!

Funny idea, wanted to write some quip on why it's bad, given the inherent polysemy, but someone already did it [1].

[1] "What’s wrong with what3words?", Chapter 3, "offends.people.easily", covers it, https://www.youtube.com/watch?v=SqK0ciE0rto

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