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Tell HN: IPv6-only still pretty much unusable

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Re: Tell HN: IPv6-only still pretty much unusable

#421

Post by error503 »

theamk wrote: post #259
throw0101a wrote: post #164

Earlier quoted context omitted.

> And regarding compatibility, with ipv4+ if you have a 0.0.0.0.x.x.x.x ip address you would be able to talk to both ipv4+ aware and legacy ipv4 devices natively without any tunneling (because you also own the legacy, non quad 0 ip address). This exists: > Addresses in this group consist of an 80-bit prefix of zeros, the next 16 bits are ones, and the remaining, least-significant 32 bits contain the IPv4 address. For…

Mayne RFC exists, but it os not used in teal world anywhere. In all servers, I configure IPv4 and IPv6 separately. Network setup is separate. DHCP daemons are separate. Firewall rules are separate. Network monitoring is separate. I would switch to that "IPv4+" system if it existed.. I am willing to use latest software/standards to future-proof my setup, but duplicating all the work is too much for me.

There are viable transition mechanisms other than dual stack, that put some kind of translation layer between protocols, rather than expect native IPv4 connectivity on all hosts.

This is perfectly viable, and is how many mobile networks handle IPv4 (ie. there is no native IPv4 on the handset at all), and how many cloud providers are handling it these days too. You have to do NAT at the border anyway, why not NAT to/from an IPv6 address?

The adoption problem doesn't have that much to do with the technology, it's simply that it provides little value to most individual entities participating in the network, even if the benefit in aggregate is clear, so it's difficult to achieve the critical mass to make it valuable. It's the same thing behind climate change and so many other societal issues.

Re: Tell HN: IPv6-only still pretty much unusable

#422

Post by School-Cotton »

throw0101c wrote: post #405
Spooky23 wrote: post #348

Earlier quoted context omitted.

You just need to do what the world did - NAT. IPv6 is more than just address space extension. There’s all sorts of stuff packed in there that complicates the process. All mobile clients are behind CG-NAT. We should have built standards around that instead of worrying about extending IP space to Mars or whatever.

> All mobile clients are behind CG-NAT. Demonstrably false. T-Mobile US mobile clients are IPv6-only and connect via IPv6 to IPv6 sites: * https://www.youtube.com/watch?v=d6oBCYHzrTA * https://www.youtube.com/watch?v=nNMNglk_CvE NAT is only used to connect to IPv4-only hosts via DNS64 (with or without 464XLAT). As of 2022Q2, T-Mobile US has 110 million customers: * https://www.statista.com/statistics/219577/total-cus…

I also have IPv6 on Verizon Wireless. (I don’t know the details of how it connects to IPv4-only hosts.)

Re: Tell HN: IPv6-only still pretty much unusable

#423

Post by Gigachad »

codegeek wrote: post #282
redox99 wrote: post #32

IPv6 has been one of the biggest failures in the last couple of decades. And I don't mean adoption, I mean the standard itself. If IPv6 were IPv4 with more octets, then we would all have been using it for like a decade. Yes, I understand it would still require some breaking changes, but it would have been a million times easier to upgrade, as it would be a kind of superset of IPv4 (1.2.3.4 can be referred as 0.0.0.0.…

I always joke with "We figured out how to move from Python 2 to 3 but we still cannot figure out how to do IPv6" :). What a catastrophic failure it has been. Should we just stop using it altogether and retire or are there people still advocating ?

IPv6 adoption is growing at 5% per year and is currently around 40% https://www.google.com/intl/en/ipv6/statistics.html

I expect as we get closer to the end we will see it pick up speed. Countries are now mandating IPv6 support as early as this month https://www.indiatimes.com/technology/news/india-sets-new-de...

Things are still moving forward, faster than ever at this point.

Re: Tell HN: IPv6-only still pretty much unusable

#424

Post by bauruine »

pifm_guy wrote: post #396
bauruine wrote: post #365

Earlier quoted context omitted.

The problem is that the routers that have to hold the routing table can only handle a limited number of routes. There is a good article from APNIC about the topic. https://blog.apnic.net/2021/03/03/what-will-happen-when-the-...

Said routers could be redesigned... And besides, there is no need to keep the whole routing table in RAM. Instead all that's necessary is a single integer per route representing which port packets to each route needs to be sent down. So even for a large router with 64 ports, the whole routing table fits inside 1 megabyte.

Sure they can create routers with more space for the routing table but you still have to replace all the old ones which isn't cheap.

A single port of a router at an internet exchange can reach more than 1000 different routers. A router has to decide to which IP it should forward a packet not just the port.

Re: Tell HN: IPv6-only still pretty much unusable

#425

Post by Gigachad »

connicpu wrote: post #224
RijilV wrote: post #9

It's been a quarter of a century since IPv6 launch. There's some really good lessons learned here. IPv6 requires everyone, everywhere, needs to change their configuration to add IPv6 addresses and network connectivity to every node/endpoint. The madness of course is that all the underlying infrastructure software (routers, OS, standard libraries) all support IPv6. It would seem, at a large enough scale, that software…

I got a brand new router recently, IPv6 was still disabled by default! I honestly can't understand the reasoning, I don't even buy the internet visibility argument because the default incoming connection rules for IPv6 after I enabled it were deny-all. We really have a long way to go still in getting equipment everywhere enabled on it.

Some ISPs have v6 enabled but it's just broken or sub optimal. I imagine the logic is that v4 always works and the user could only see a benefit from having v6 off by default.

Re: Tell HN: IPv6-only still pretty much unusable

#426

Post by Dagger2 »

lee101 wrote: post #366

I just like to call out Starlink for not supporting ipv6, massive headache as calls to various ipv4 only sites fail in python then you need to set a timeout in your request to trick python into falling back to ipv4, also no public adresses on Starlink made self hosting https://text-generator.io a pain but CloudFlared tunnels helped

Starlink are working on it; they've turned on v6 in lots of places over the past month or so.

Although you shouldn't need to do any special handling for v4-only sites on v4-only networks. Your DNS results should be sorted to put v4 at the top in that case, so it should be tried first.

Re: Tell HN: IPv6-only still pretty much unusable

#427

Post by usr1106 »

ipython wrote: post #314

I have to say I’m super disappointed in the ignorance and negativity in the comments on this thread. Ignorance of both the difficulties inherent in upgrading a fixed size wire protocol designed for a research network fifty years ago, and the widespread adoption of ipv6 for real customer deployments. Heck most of you are probably using ipv6 through your mobile carrier and don’t even know it!

> most of you are probably using ipv6 through your mobile carrier and don’t even know it!

My mobile carrier provides dual stack (with NAT in the IPv4 side). So no problem with any kind of site. Are there operators who provide IPv6 only? Haven't really read up on that topic, but I guess that requires NAT64 because the average user needs to reach IPv4-only sites. Does that generally work well?

If yes, why can the poster of the submission not use that on his Hetzner instances?

Re: Tell HN: IPv6-only still pretty much unusable

#428

Post by error503 »

est31 wrote: post #157
redox99 wrote: post #32

IPv6 has been one of the biggest failures in the last couple of decades. And I don't mean adoption, I mean the standard itself. If IPv6 were IPv4 with more octets, then we would all have been using it for like a decade. Yes, I understand it would still require some breaking changes, but it would have been a million times easier to upgrade, as it would be a kind of superset of IPv4 (1.2.3.4 can be referred as 0.0.0.0.…

One of the ideas of ipv6 was to reduce routing tables, those tables that backbone providers have to keep in memory and look up for incoming traffic. With ipv4's fragmented allocation scheme, these routing tables are huge. With ipv6, even huge companies like amazon only have a couple of global allocations. A "ipv4 with more octets" scheme would have kept that fragmentation around. That being said, Amazon currently has…

Amazon is really not a great example, I don't think. The giant cloud providers are outliers with respect to DFZ announcements, as they have many, many POPs and also allow their customers to announce address space. They're more like transit networks at this point than what could be reasonably considered a representative end user.

More reasonable to look at announcements per AS, where it's currently about half of IPv4, but trending upwards at a faster pace.

v6: https://www.cidr-report.org/cgi-bin/plota?file=%2fvar%2fdata... v4: https://www.cidr-report.org/cgi-bin/plota?file=%2fvar%2fdata...

Re: Tell HN: IPv6-only still pretty much unusable

#429

Post by nottorp »

yesco wrote: post #400
nottorp wrote: post #335

Earlier quoted context omitted.

Not clear. How do i reach a device in my local network? Via the optional internal address if my uplink is down and via my link-local address if my uplink is up? Is the link-local address any good if i'm on wifi but want to ssh into a wired host in my home? Are you getting my point yet? Edit: actually I won't wait. The point is it's needlessly overcomplicated. It was done by a commitee that didn't even consider people…

> Is the link-local address any good if i'm on wifi but want to ssh into a wired host in my home? Lets breath and think about this for a second, you want to know how to reach a device on your local network, your host has a "link-local" address. Could there be a connection here? The answer is yes because it's in the name, it's literally in the name, why are you confused? What is over complicated about this? Back when…

> your host has a "link-local" address. Could there be a connection here?

Maybe. Or maybe not. It could apply only to hosts connected via the same switch? Or same AP? That's how i read link-local. It's obvious to you because you already know.

> see your complaints about complexity as nothing but the whining of a child

So point me to an overview of ipv6, enough to manually configure a small network, that is clear and complete. Not the RFCs please, I don't want to learn to configure an enterprise (or university) network.

Last time I searched for one there wasn't one.

Re: Tell HN: IPv6-only still pretty much unusable

#430

Post by error503 »

fernandomm wrote: post #191
redox99 wrote: post #32

IPv6 has been one of the biggest failures in the last couple of decades. And I don't mean adoption, I mean the standard itself. If IPv6 were IPv4 with more octets, then we would all have been using it for like a decade. Yes, I understand it would still require some breaking changes, but it would have been a million times easier to upgrade, as it would be a kind of superset of IPv4 (1.2.3.4 can be referred as 0.0.0.0.…

Let's not forget about the idea that ISPs would distribute a /56 range to residential users. You could split it in /64 ranges according to your requirements and everything would work fine. There is only one "minor" issue: all major ISPs in my country ( Brazil ) only provide a single /64. You can't get another /64 unless you upgrade to a very expensive business plan. That makes IPv6 not only useless but also a huge se…

Why can't you use it as a firewall? It's weird, and against RFCs for your ISP to only give you a /64, but that should still be routed address space is routed through your router/firewall box, and therefore trivial to firewall with the normal tools. This is also pretty much the necessary topology, because if the box needs to do NAT for IPv4, it needs to terminate the address on the firewall too. You'd need separate interfaces to do some scheme where IPv6 was layer-2 to the ISP, and IPv4 terminated at the firewall.

Most/all such boxes, especially those deployed by ISPs, have a stateful firewall with an allow-out deny-in policy in place by default. I've never seen otherwise, but I guess it's possible?

Back in the day, cable modems didn't include a 'router' and lots of users plugged their Windows XP PCs into them and got compromised. Most weren't really blaming the ISP for this; go buy a router they said. And some providers will still just give you a public IP with full access by default when you plug into their demarc equipment; indeed many users want this because that's what Internet access should be. Security is on the end user. I don't see this situation as any different, though your ISP should know better than shipping insecure-by-default, this isn't really a problem with the protocol.

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