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Tell HN: IPv6-only still pretty much unusable

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431–440 of 649 posts

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

#431

All ipv6 shortcomings discussion aside; What I think is the more vital problem to focus on is that the governments clearly don't want us mere mortals to expose our own servers running on our own hardware to the outside world (most often justifying that with "it's for your own security" mantra, for we're all deemed too dumb to figure that out for ourselves). ISP-imposed ipv4 double NAT (imposed on ISPs by the governme…

CGNAT isn't imposed by governments, it's imposed by address space exhaustion in v4. v6 fixes it by having enough address space that NAT isn't needed. Governments share some responsibility here for not mandating a move to v6, leaving everybody in "wait for other people to go first" mode, and one might ask why they've done that but the answer is mostly that governments don't usually get involved in the Internet at that…

>If they wanted to prevent inbound connections then all they would need to do is firewall them.

Note that this already happens to an extent. Some ISPs try to protect their users from UPNP attacks and block certain inbound ports. On the outbound side, many ISPs ban port 25. ISPs could have easily claimed security and limit inbound connections far more - but the reasons for these limits are apparently money+security and not a secret government mandate, so they didn't limit everything.

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

#432

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 poste…

T-Mobile has been IPv6-only for a while.

I guess you can't use NAT64 at Hetzner because Hetzner doesn't provide it.

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

#433

Earlier quoted context omitted.

> Imagine I own a company and I already have a bunch of IP4. I upgrade my network equipment to IP4+, and then keep all my routing and firewall configs. Everything just works the same as before. Now I want to access IP4+, so I add a route entry for all the IPs above 255.255.255.255. It does not. Because 255.255.255.255 only covers 32 bits and "IP4+" is >32 bits. You'd still have to touch every rule to to tweak the mas…

I still don't understand why they shifted from 0:: to ffff:: but point stands, ipv6 is exactly ipv4+, except yes, they did redo arp. I don't think its really that much better...but really? that's what turns something from great into awful?

> I still don't understand why they shifted from 0:: to ffff::

I think the most reasonable explanation is probably because they thought ::1 being loopback (otherwise it would have to go above 255.255.255.255) was more important (since it would exist as long as IPv6 does) than the transition encoding that presumably would die off over time.

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

#434

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 poste…

Yes, T-Mobile for example. I just dumped the interface information from my iPhone and the only address available is an ipv6 address. Everything else is put through an ipv6 to ipv4 gateway. Works fine.

Apple has required app developers to support ipv6 only deployments since 2015: https://developer.apple.com/support/ipv6/

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

#435
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.…

>If IPv6 were IPv4 with more octets, then we would all have been using it for like a decade.

The only real reason v4 is being replaced after decades is that it has a single showstopping flaw - the lack of addresses. v6 solves this forever with its massive address space. We've seen how incredibly hard replacing v4 has been. Without a similarly huge flaw to drive a replacement it's very possible that v4's successor could be the universal internet protocol for hundreds or even thousands of years. With that in mind, even though progress has been frustratingly slow, going for something closer to the global maximum in design and avoiding ease-of-adoption hacks might be the right thing to do.

That's not necessarily to say that your suggestion of still using dot-separated numeric values would be objectively worse, but bear in mind that doubling the number of fields from 4 to 8 as you've done only gives you a 64-bit address space, whereas IPv6 as it exists has a 128-bit space, so would require something like 0.0.0.0.0.0.0.0.0.0.0.0.1.2.3.4.

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

#436
post #400

Earlier quoted context omitted.

> 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…

Yes link-local is only local to the link (same broadcast domain).

But most home networks are bridged on layer 2 anyway.

IPv6 allows for a design where you don't have everything on the same broadcast domain but actually use subnets for e.g. the WiFi network. But since you still want to retain IPv4 compatibility, this is usually not an option in home networks.

> So point me to an overview of ipv6, enough to manually configure a small network

Just enable router advertisements on your router (likely already the case) to announce a /64 prefix that was derived from the prefix you got from your ISP. You also want to enable RDNSS so DNS server information is included with the router advertisement. (also usually the default)

Then enable SLAAC on your hosts (already the default) to automatically select an address based on the prefix from the router advertisement. A /64 is big enough that the router doesn't have to individually assign addresses. Hosts can just pick one and if they are polite, ask if it's already used by someone else (duplicate address detection).

Presto! You now have IPv6 connectivity.

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

#437

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 poste…

I had IPv6 only on the default APN configuration pushed by my carrier on Android, last time I checked it And IPv4 only for roaming Both v6 only, v4 only and v4+v6 were supported

For landlines, I'm surprised because some ISPs who were not having difficulties with ipv4 are being the fastest to switch to ipv6. While some who had to deal with CG-NAT and other horrible stuff are fine with ipv4, and haven't yet planned to move to ipv6

Is this due to corporate culture or something ?

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

#438

Earlier quoted context omitted.

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.

True, on an individual level that probably represents the best benefit. Anyone who actually cares would also know to go through the settings to check the defaults on all of those things with a new router too.

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

#439
post #382

Earlier quoted context omitted.

All the big cable and fiber internet providers I've worked with in the US support IPv6, even evil nasty ones like Comcast have supported it for a decade now.

Is it enabled by default on customer equipment?

When I had Comcast about 5 years ago it was enabled by default.

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

#440

I was thinking about ipv6 the other day. I concluded in my head that adoption was just around 5-10%. Luckily I went to verify that with statistics. https://www.google.com/intl/en/ipv6/statistics.html While price of ipv4 addresses are increasing, the world has slowly been adopting ipv6. From the graph above, I'd say we cross over 50% in about 2-3 years time. At some point the "dash" to adopt ipv6 starts, and brave fol…

At previous gig already seen some isps in India that are ipv6 only
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