Comment by sqrt17 | Hacker News Reader

Comment by sqrt17 | Hacker News Reader

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IPv6 has been the future for quite a while (2002), and it will probably remain the future for quite a while because we have good partial solutions:

* The HTTP Host: header means that you don't need a public IP address for every site. Heck, it would even be possible to have a single public IP for a load balancer that redistributes requests to a data center full of servers that serve requests for thousands of sites. If you think this can't be done efficiently, think about these Cnoection: and oCnnection: headers that pop up with load balancers that only rewrite part of the header.

* NAT means that we only have one IP per Internet-connected household, not one per computer or other device. With mounting pressure, mobile operators will increasingly put their users behind NAT and maybe some people in address-starved regions of the world will only be able to get NATted connections from their provider. Software like Skype knows how to get around NAT pretty well, and UPnP works pretty well for other server-like programs that people have.

Which means that 99% of the people will be perfectly happy with multiple-occupancy HTTP service and UPnP/firewall piercing and not care at all whether IPv4 addresses run out or not. The remaining 1% will have to push very hard, and pay a significant fraction of the cost, to get IPv6 off the ground all while the incumbents sit in a corner and watch.

The problem is that we have fewer IPV4 addresses then we have consumers who wish to consume IPv4 content.

Take our current situation: We still have large swaths of china and india without Internet connectivity, yet we are basically entirely allocated with demand for ipv4 addresses increasing.

V6 used to be hard to implement because older routers/switches implemented their support in software rather then in ASIC. This is now no longer an issue, which is why you see ipv6 connectivity sprouting up around the place. I would expect that when push comes to shove, we will see a fast v6 transition when it becomes a large enough deal for there to be > 0 consumer demand for it.

My prediction is that, if large swaths of China and India get Internet connectivity, they, or their internet providers, will have to choose between

* NATted IPv4 connectivity (maybe with one IP per city and not one per household) and

* buggy but non-NATted IPv6 connectivity.

with the former being cheaper to implement. Most likely, IPv6 will only see universal adoption after the old gear that has buggy or too-slow IPv6 support has been thrown out. Then again, if a large government (say, China) puts itself behind IPv6 (say, because having one IP address per citizen is more convenient for keeping tabs on everyone), a fast transition would be more likely.

Don't get me wrong here: I think that the transition to IPv6 will happen eventually, but not as fast as the shrinking number of remaining IPv4 address blocks would suggest.

From what i've heard, carrier grade nat is stupidly expensive and rather hard to scale nicely at reasonable speeds.

It would be fairly easy to implement say ipv6 in china, as it would be a closed system with everybody getting new gear and everybody in the same "we have no ips" boat.

To be honest, as the internet ecosystem in places such as china is mostly closed, I'd be surprised if they didn't go ipv6 only internally well before the rest of the world switches (what's the point in having a v4 address if everything you care about is on native v6 and you have a 64 gateway for everything that isn't).

Going to be interesting to see.

Sure, people are currently happy with the current state of affairs.

That's different from hoping that IPv6 will fail, like the original poster did.

btw:

- Tricks like HTTP host header partial rewriting cannot be done with HTTPS. Sure, there's SNI, but that doesn't change the bottleneck problem.

- One IPv4 per household will be possible in USA, but other countries have much less IPv4 addresses. There's just not enough of them, and artificial scarcity makes no sense at all.

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