IPv6 is the only way forward

https://ankshilp.in/posts/for-the-love-of-internet/

by quaintdev • 4 months ago

104 329 4 months ago

mono442• 4 months ago

The main problem with IPv6 is that it is different from IPv4. There's SLAAC, there's no ARP and there're also some other differences. In the end, it's simpler to just not bother.

dogleash2• 4 months ago

Yup. People learn parts of v4 through osmosis because it's the default. Then when networking topics come up, it's easier to keep going with stuff that looks familiar rather than un-learning assumptions. Why bother with the weird other thing that's not even mandatory?

general146510• 4 months ago

Because IPv4 is logical and makes sense. First thing which IPv6 came up with? No NATs everything will have a public address. It turned out that this was hare brained idea so let's just cover it up with firewall. However misconfigured firewall means that everything is open... IPv6 has been designed by people who were unable to think further than what is going to be tomorrow for a lunch.

jcgl7• 4 months ago

ARP-schmarp. That doesn't matter to almost anyone who doesn't need to go deep into the network.

But yeah, SLAAC's paradigm of moving assignment logic into the node (away from network infra like in DHCP) is definitely a stumbling point.

labcomputer5• 4 months ago

IPv6 ND (and SND) serve the same purpose as ARP. It's like saying a fancy French restaurant doesn't have a cook because it has a chef.

lgunsch• 4 months ago

If IPv6 was going to be successful, it would have been successful years ago. It seems, people are just more comfortable with layers of NAT than native IPv6 everywhere. I'd guess that it should have been more backwards compatible. Similar to UTF-8 and ASCII.

BenjiWiebe8• 4 months ago

My Verizon connection has a CGNAT IPv4 and a publicly routable IPv6 address. It's at least partly a success, if you're using a cell phone on Verizon in the US.

jdwithit• 4 months ago

IPv4 has been "in crisis" for the entire 20 years I've worked in tech and we seem to be managing alright. Not to say things can't be better or we shouldn't try to improve. But I'll be surprised if v4 isn't still the default for most use cases in another 20 years.

RiverCrochet• 4 months ago

That's because the Internet is basically broadcast TV 2.0 so no one cares about having public IPv4's at home as long as they can get to their memes and streaming. Great job, we took something that was meant to be a next frontier in humanity and let anyone connect with anyone else without gatekeepers/intermediaries and turned it 21st century brainrot troughs. Perhaps a society not in slow intellectual decline would have chosen otherwise.

ozim2• 4 months ago

I do agree.

But at the same time there is a quote by Stanisław Lem...

"Until I used the Internet, I didn't know there were so many idiots in the world"

ux2664782• 4 months ago

Great job, we took something that was meant to be a next frontier in humanity and let anyone connect with anyone else without gatekeepers/intermediaries

We already had that, it's called shortwave radio. The internet, especially as it's implemented and as it's used, is a terrible way to achieve this. It's service providers the whole way down.

dartharva• 4 months ago

Perhaps a society not in slow intellectual decline would have chosen otherwise.

The "slow intellectual decline" has circular causality with advancement of mass media and convenience tech.

lern_too_spel3• 4 months ago

His point is that you're managing alright because you live in a country where your ISP can give you a public IP address. The author lives in a country where that is not possible and accesses the Internet behind layers of NAT.

LoganDark8• 4 months ago

What's the difference, other than port forwarding? Does NAT cause some sort of unique issue that makes existence miserable?

wmf7• 4 months ago

It's possible for Indian ISPs to buy IPv4 addresses and assign them to customers. Maybe not for $5/month but if you're willing to pay US prices (plus tax) you should be able to get US quality service.

netdevme• 4 months ago

You can even buy a block, but the smallest one has 256 addresses.

me4502• 3 months ago

Part of the issue is this affects different countries differently, based on residential IP allocations to household ratios. I am currently on CGNAT in Australia split 256 ways, and any site that doesn't support IPv6 can be borderline unusable. I can't imagine what it's like in countries with worse ratios, like India.

It's been in crisis for decades, but it's also getting increasingly worse every year.

rectang• 4 months ago

If UTF-8 represents the triumph of a design prioritizing backwards compatibility with an existing standard (ASCII) to facilitate a transition, then IPv6 is the cautionary tale of a design which could have made the transition simpler but did not.

w3ll_w3ll_w3ll• 4 months ago

IPv6 cannot be backward-compatible with IPv4 in the way UTF-8 is with ASCII. Any argument built on that comparison reflects a misunderstanding of the protocols and leads to flawed conclusions.

AussieWog932• 4 months ago

Wait, why couldn't it?

Just split the address into two 32-bit chunks (call the top word the "pool", bottom word "address") and assign the full IPV4 range to pool 0x00000000. Done.

jcgl7• 4 months ago

Yep. Translation technologies like NAT64 and company basically as good a job as can be hoped for. And they're quite good nowadays!

But to stick with the ASCII->UTF-8 comparison: how would you have done the transition if you had to stay within ASCII's size of 7 bits?

j1elo2• 4 months ago

Why not? Sincere question. As a very superficial idea, if we go back to the drawing board, for example we could decide our new cool concept of address to be an IPv4 + an hex suffix, maybe at the expense of not having a humongous address space.

So 10.20.30.40 would be an IPv4 address, and 10.20.30.40:fa:be:4c:9d could be an IPv6 address. With the :00:00:00:00 suffix being equivalent to the IPv4 version.

I just made this up, so I'm sure that a couple years of deep thought by a council of scientists and engineers could come up with something even better.

commandersaki4• 4 months ago

This recent article begs to differ: https://news.ycombinator.com/item?id=47352236

functional_dev• 4 months ago

Backwards compatibility point is interesting.

Found this visual breakdown of IPv4 -> IPv6 transition.

Dual stack and tunneling sections show how much complexity came from not having a clean migration path - https://vectree.io/c/ipv4-vs-ipv6-address-architecture-nat-a...

Dagger218• 4 months ago

But there is a clean migration path to v6: you deploy it. How much cleaner can you get?

leosanchez• 4 months ago

Author if you are reading comments, rss feed entries point to example.com

haddr• 4 months ago

the link to the full table somehow doesn't work for me

quaintdev2• 4 months ago

Fixed

quaintdev2• 4 months ago

Thanks! Check now.

bombcar2• 4 months ago

I don’t know how you measure “metric tons of content” but I suspect in general there’s lots of US-available content on IPv4 that the countries like China and India want to access, and not much the other way around.

But that should be a perfect playground for an IPv6-only network that has gateways to the IPv4 content; eventually the home-developed content will begin to drive demand elsewhere.

nickserv• 4 months ago

Yes, there's lots of content on IPv4, and there is also a lot of traffic from India...

If India were to turn off IPv4, it would be a great incentive for IPv4-only sites in the US and Europe to add an IPv6 address.

wmf7• 4 months ago

No mention of Indian ISPs just buying IPv4 addresses. Prices are even declining.

isodev2• 4 months ago

Someone should’ve thought about the UX of IPv6 before declaring it to be “the way”. It’s like having to learn Klingon just to setup your printer. IPvNext could sort that out… maybe it’s time to consider moving on.

bluGill5• 4 months ago

People claim this all the time, but every time I push I discover they have no clue how networks work and just handwave away as "easy" or "details" the very reasons people who understand networks say it can't work.

isodev2• 4 months ago

I think you’re making my point - someone decided to surface a very low level concept “as is” (without a suitable abstraction) on a level where people also need it for use cases that don’t justify knowledge of the arcane. Or dealing with gatekeepers for that matter.

dogleash2• 4 months ago

every time I push I discover they have no clue how networks work

Listen here, if there is a networking technology or feature that I wasn't forced learn when I half-assed a SOHO router config in 2005, then it shouldn't exist at all.

9rx• 4 months ago

but every time I push I discover they have no clue how networks work

Obviously. Anyone who does understand how networks work aren't going to spend any time talking about it. People don't talk about things they are certain about. They talk about what they don't know much about to feel out what they're missing. You will never find a discussion where pushing back reveals that you found the world's utmost expert. The world's utmost expert is bored with the subject and has moved on to talking about the things he has gaps in.

IsTom2• 4 months ago

Like there was any chance to see UX of this to work or not in most of places. I've never had an ISP that even offered any IPv6 connectivity besides mobile internet.

wmf7• 4 months ago

SLAAC + mDNS makes IPv6 basically invisible.

izacus• 3 months ago

If by invisible you mean "things randomly won't work and you'll smash your head in the wall trying to figure out why".

unethical_ban• 4 months ago

I learned the basics of IPv6 a few years ago, and forgot some of it... but NDP, the built in default addresses for router solicitation, address assignments and so on.

I'll tell you that if you just think of it on its own, it's really no harder than IPv4 + ARP + DHCP, just one or two extra things to remember.

The difficulty of adoption is the featureset and the UX of operating systems and home routers in particular. It is really difficult to find a consumer router, or even home networking OS, that exposes sensible working defaults for IPv6. The problem extends to the ISPs.

The spec is fine.

azalemeth• 4 months ago

I am behind cgnat but have a native ipv6 /64 at home. I've got a great fibre connection (2G5) and everything "just works". I can host on ipv6 native machines and see them from anywhere in the world that has native ipv6 access.

The trouble is that 1) my employers do not have native ipv6 access; 2) neither does my mobile connection; and 3) really nor do a lot of my friends. Moreover, 4) if you browse a website from a native world-reachable ipv6 address, you're fingerprinted by it and it's overwhelmingly unique to you. So, it doesn't really work for hosting, and I don't get any direct benefits from it.

Instead I have a vps with a public ipv4 address and have a router that creates a wireguard tunnel to it. The reverse proxy works great over ipv6 and I am now in a position where I can forward ports and have direct connections -- albeit with hugely increased technical complexity. Ipv6 has many great ideas in it. If it's universally used it might just catch on...

BenjiWiebe8• 4 months ago

I'm curious - which mobile provider? I thought they were the ones that use IPv6 most, some even using 464XLAT so your device only has a v6 address.

vimredo4• 4 months ago

4) if you browse a website from a native world-reachable ipv6 address, you're fingerprinted by it and it's overwhelmingly unique to you.

IPv6 privacy extensions exist & are enabled by default in most (if not all) operating systems today, which (this is my understanding; take it with a grain of salt) create what essentially are extra IPv6 addresses, used for outbound traffic, that aren't generated via your MAC address.

bluGill5• 4 months ago

The US doesn't have excessive IPv4 Addresses. We have a real shortage and big pain because we don't have anywhere near enough. Sure we have 40% of them all - but that has no indication of what enough is.

blinded2• 4 months ago

100% this, my college had 2 /16s for no reason. The printers were all public, was a mess.

miladyincontrol• 4 months ago

I mean having a public address doesnt mean it has to be publicly routable. Same thing applies to ipv6.

I speak as someone who worked at an institute that had similar abundance of address space.

wpm3• 4 months ago

My workstation used to have a public address system it was awesome.

sassymuffinz• 4 months ago

I worked at an ISP way back in the dark ages of 2008 and we were all worried about IP exhaustion then. It's now 17 years later and what do you know, IPv4 is still trucking.

icedchai2• 4 months ago

I think we'd be surprised how much address space is actually wasted, not announced or routed.

I have my own /24 that I registered back in the 90's. It is, in fact, routed and announced globally. I know several "early Internet" nerds with the same.

I know three local companies with /16's that aren't even announcing their blocks! Perhaps they use them internally.

tonymet16• 4 months ago

There are countless threads online on forums like Hacker News, Reddit where people who never really got comfortable with idea of IPv6

It’s clumsier than ipv4. It’s unnecessary since NAT was invented. In practice IPv6 requires dual stack, which means twice as many firewalls, names and routes to manage — so 4x the debugging because you have 2 dimensions that can either be working or failing. Addresses are too long to remember, too clumsy to write, and after 30 years still don’t have consistent representation (how many colons and brackets?).

Look, IPv6 has some benefits, but until the usability is fixed, it will be another 30 years before it’s close to 95% adoption.

apearson2• 4 months ago

To reduce doing things twice there is NAT64/646XLAT. How many v4 addresses have you memorized, I normally use DNS or mDNS.

tonymet16• 4 months ago

that reduces part of the scope for some of the customers

Chu4eeno• 4 months ago

... and annoying casting from `sockaddr` to either `sockaddr_in` or `sockaddr_in6*` while you pass around a socklen_t.

10 years ago I was all gung-ho about IPv6, but it's annoying at every level.

tonymet16• 4 months ago

Having 2 sockets for loopback or multiple interfaces is a huge pain

Dagger218• 4 months ago

Why are you casting to sockaddr_in/6? The whole point of that system is that you can just pass around the sockaddr* without even needing to have a definition for sockaddr_in or sockaddr_in6. All of the socket API functions accept sockaddr*, and if you need to get the IP or port out then you use getnameinfo(), which also takes sockaddr*. There should be little reason to ever cast to either of those types in normal use. (I can think of one or two cases where you might, but they're not common.)

Having to deal with the separate socklen_t is mildly annoying, but you can just make a little struct that holds both.

throw0101c8• 4 months ago

It’s clumsier than ipv4. It’s unnecessary since NAT was invented.

This is a privileged view of someone whose ISP has enough money (or was around early enough) to get enough IPv4 addresses to assign one to every customer's WAN interface. Not everyone is so lucky.

A lot of folks get non-publicly-routable 100.64.0.0/10[1] on their WAN interface with no way to do hole punching because they're behind CG-NAT.

[1] https://en.wikipedia.org/wiki/IPv4_shared_address_space

tonymet16• 4 months ago

so ipv6 is now a social justice issue? I'll send you the $2 a month for a elastic IP .

Hikikomori6• 4 months ago

Why would you be typing of remembering ipv6 addresses? Representation has always been consistent, if you learn the rules, like how 1337::1/64 is a valid address.

tonymet16• 4 months ago

that address doesn’t even work in the address bar

oconnore• 4 months ago

I don't understand why people are so negative about IPv6. I have done essentially zero home networking work and I just ran this successfully. It just works!

``` > ping6 google.com PING6(56=40+8+8 bytes) 2605:59c0:236f:3a08:7883:9d04:c26d:5fa1 --> 2607:f8b0:4005:806::200e 16 bytes from 2607:f8b0:4005:806::200e, icmp_seq=0 hlim=117 time=22.262 ms 16 bytes from 2607:f8b0:4005:806::200e, icmp_seq=1 hlim=117 time=26.124 ms 16 bytes from 2607:f8b0:4005:806::200e, icmp_seq=2 hlim=117 time=26.807 ms ^C --- google.com ping6 statistics --- 3 packets transmitted, 3 packets received, 0.0% packet loss round-trip min/avg/max/std-dev = 22.262/25.064/26.807/2.001 ms ```

kstrauser7• 4 months ago

That's literally impossible, to hear some people tell it. "And also, look how hard it'd be to memorize that address", say the people who remember like 2 IPv4 addresses, one of them being 127.0.0.1.

NekkoDroid• 4 months ago

I remember like 10 different IPv4 addresses, 6 of which are DNS servers where each octet is a single number, 1 is my router, 1 is my home network switch, 1 is my home server and the last one localhost.

The main thing all those have in common is they are either something I frequently use (all mentioned local IPs) or just stupid easy to remember (DNS servers), neither of which isn't possible for IPv6.

From memory isn't localhost for IPv6 not shorter than for IPv4? The answer is yes, it is ::1 and I was thinking of the Multicast and Link-local address prefixes which are ff00:: and fe80:: respectively.

jen729w• 4 months ago

Tailscale, perhaps ironically in this context, has shown me the value of not caring about an IP address.

I used to. When I had a home network I'd carefully assign `10.52.1.x` where `x` was the periodic number corresponding to the machine name! (I write from `lutetium`.)

Now, with Tailscale's magic DNS – `lutetium` being all I need – why on Earth would I give a crap about an IP address? I've gone from being obsessed to truly not caring at all.

So, give me IPv6. Auto-assign everything! All I want is a name.

itopaloglu83• 4 months ago

When people are managing 20 devices on a network, they access everything by IP address directly and struggle with constant DNS issues.

Introducing a more complex system without easing any of the cognitive load and making fun of it is just cruel at this moment.

Users need a simpler way to connect to their devices, and what tailscale did with magic dns shows that users don’t even care about IPv4 they just want to connect to their devices with something simple they can remember.

magicalhippo5• 4 months ago

I don't understand why people are so negative about IPv6. [...] It just works!

Networking is a lot more than being able to ping a single host.

As a concrete counter-example, IPv6 routinely broke for me when I was using pfSense as a router. Why? Because pfSense, with no way of disabling this behavior, published its public IP as the DNS server for internal clients.

So each time I got a new prefix from my ISP, which happens about once a week or more often, machines stopped being able to perform DNS lookups for hours or until I rebooted them.

And, if I had bothered configuring IPv6 firewall rules, those would have had to be reconfigured manually with the new prefix. I understand this is mostly fixed in pfSense recently, but this was the case for many, many years.

Another counter-example is that Android only supports SLAAC, and SLAAC only supports providing a few key infrastructure details like router and DNS. If you want to tell the Android client something else, like NTP server, you're outta luck. Also, if Android successfully gets an IPv6 address via SLAAC, it requires the DNS server IP to also be an IPv6 address. So your internal DNS server must then also serve on IPv6. If that wasn't the case, it would just silently use Google's own DNS servers, breaking any local configuration you had.

Another point is that a lot of us tried using IPv6 decades ago, and so we still have scars from that time. IPv6 today is a lot better, but I still have a lot of IPv6 frustration associated with it from 15-20 years ago.

happymellon• 4 months ago

As a concrete counter-example, IPv6 routinely broke for me when I was using pfSense as a router. Why? Because pfSense, does really bad things.

I mean, I have a router that is trash with IP4. Therefore IP4 is trash!

MaKey2• 4 months ago

And, if I had bothered configuring IPv6 firewall rules, those would have had to be reconfigured manually with the new prefix. I understand this is mostly fixed in pfSense recently, but this was the case for many, many years.

Why would you have to reconfigure your firewall rules when you're getting a new IPv6 prefix?

thomasdziedzic2• 4 months ago

IPv6 feels like we just can't admit to ourselves that it has been a failed transition. What would it take to come up with IPv7 which takes in the lessons of IPv6 and produces something better that we can all agree is worth transitioning to over IPv4.

apearson2• 4 months ago

What changes to IPv6 would you make to make it easier to transition?

general146510• 4 months ago

Whole model same as IPv4 (DHCP, NAT, ICMP, DNS, ...) just in v6. If IPv6 and IPv4 would be essentially the same from the get go, IPv4 would be a niche 20 years.

Sure everything above IPv6 have, but it took years and years of screaming to get it.

plqbfbv• 4 months ago

What would it take to come up with IPv7 which takes in the lessons of IPv6 and produces something better that we can all agree is worth transitioning to over IPv4.

The only lesson to learn from IPv6 deployment is that if there's a workaround available and the world isn't burning, it'll take 30 years from initial design to actual adoption. So if you went out and took 10 years to design IPv7, it'd likely take until 2070 for it to gain some adoption. This is because big network hardware is costly and has very long replacement cycles.

IPv6 was already designed as a lessons-learnt protocol from IPv4 issues. The header is greatly simplified and it's more hardware-friendly, it incorporates the required features into the protocol and leaves extensibility as an optional add-on that doesn't slow down routing packets, all the while granting an infinite address space.

throw0101c8• 4 months ago

IPv6 feels like we just can't admit to ourselves that it has been a failed transition. What would it take to come up with IPv7 which takes in the lessons of IPv6 and produces something better that we can all agree is worth transitioning to over IPv4.

Per Google, quite a few countries (including the US) are at >50%:

* https://www.google.com/intl/en/ipv6/statistics.html#tab=per-...

Every handset on T-Mobile US's network gets IPv6 (and they're not the only carrier like that):

* https://www.youtube.com/watch?v=d6oBCYHzrTA

So I'm not quite sure where "failed" enters the equation.

And what exactly would be different with IPv7? Anything that needs more address bits would have to update DNS to create new resource record types ("A" is hard-coded to 32-bits) to support the new longer addresses, and have all user-land code start asking for, using, and understanding the new record replies. Just like with IPv6. (A lot of legacy code did not have room in data structures for multiple reply types: sure you'd get the "A" but unless you updated the code to get the "A7" address (for "IPv7" addresses) you could never get to the longer with address… just like IPv6 needed code updates to recognize AAAA, otherwise you were A-only.)

You need to update socket APIs to hold new data structures for longer addresses so your app can tell the kernel to send packets to the new addresses. Just like with IPv6.

WorldMaker4• 4 months ago

The only place the IPv6 transition seems to be failing is in "command-and-control" corporate networks. (A majority of home/consumer/cellular users are quietly using IPv6 by default every day, per most statistics.) The lessons to be learned there don't seem to be technical but economic incentives.

Big companies believe that they have plenty of IPv4 space, especially because they've always been lax in how they read IPv4 RFCs and use IPv4 routing behind corporate firewalls. Big companies also have the most cash to buy IPv4 blocks as they go to auction. Big companies have massive firewalls and strict VPNs which also insulate them from IPv4 scarcity.

IPv4 leases don't impact enough companies' bottom lines today that they need to assess IPv6 support.

Solving those economic incentive problems would likely be a massive sociopolitical problem: you would need IANA and the RIRs to agree to inflate costs in various ways (and in the short term that might have done a lot of harm to small countries already facing IPv4 inequity and their RIRs that lost the very earliest IPv4 assignment lotteries). You'd probably need new RFCs and political enforcement to support things like "taxing" company to company IPv4 block assignments. You'd probably need collusion or regulation from the big "Cloud Providers" to enforce higher costs on IPv4-only networking.

It would take those kind of "strong handed" tactics to speed up IPv6 adoption in corporate networks. Waiting for the "invisible hand" of the "free market" can be very slow and takes patience. That's mostly what we've been seeing with IPv6 adoption: the "invisible hand" is a lot slower than some people predicted. Especially engineers that hoped technical superiority alone would be a market winner.

globular-toast2• 4 months ago

IPv6 is totally an equality issue. If a sizeable proportion of this forum had to share an IP address we would've had IPv6 done years ago.

tcaxle• 4 months ago

I agree. If you click through to the original Wikipedia table that's cited in this article you can see a pretty clear correlation between countries with more IPv4 addresses than people vs. wealth/hegemonic clout of the country. In the UK, US, Germany, France, Canada, Japan, etc. there are way more than enough IPv4s to go around. Some ISPs here in the UK will even lease you bundles of four or eight IPv4s for very little additional cost.

ux2664782• 4 months ago

The way forward for what though? It remains to be seen if this level of infrastructure and complexity has any kind of resilience. I seriously doubt it does, looking back on history. I think it's far more likely that the post-industrial population contraction (which hasn't even really begun) as well as climate change (anthropogenic or not) will make it far more likely that this model of "everybody uses a computer" ends up in the junk bin of history. Can't say I'd be sad to see it go. Somebody who has no interest in computers shouldn't ever have to touch one.

jmyeet• 4 months ago

I find it fascinating how these key technologies handle upgrades and breaking changes. For example, Python eschewed breaking changes through 2.7.x but the dam has burst since 3.0 and every point release (it seems?) makes breaking changes, sometimes reversing itself (eg the whole s/u string prefix thing).

Many here will be familiar with the second system effect [1]. Usually people want to avoid making breaking changes but once they do, they can go a little nuts. My personal opinion is only major versions should make breaking changes and a lot of thought should go into making them as painless as possible.

IPv6 is fascinating for these reasons but also that it's a product of its time in two main ways:

1. It doesn't do anything about roaming because that wasn't an issue in the 1990s but it certainly is now;

2. A 64 bit address space would've basically been infinite addresses but instead they went with 128 bit addresses (rolling in ports) but then giving individual users a /64 address range. For some reason people deny it now or simply weren't aware but that too is a historical artifact because it was intended to put a 48 bit MAC address into that space but later we realized that's a huge PII and tracking issue; and

3. History has shown that upgrading network backbone hardware (in particular) is incredibly difficult through a process that's been described as "ossification", which is a nice description. Basically, network relays and routers wanted to avoid security issues and decided to discard things they didn't understand.

That's interesting because it violates Postel's Law [2], which basically says be liberal in what you accept and conservative in what you send.

But this shows up in all sorts of interesting ways, like it's practically impossible to reliably use MTUs larger than about 1536. When IPv4 was designed, that wasn't an issue. With 1-100G+ networks it is. There are RFCs about using large MTUs but you're dependent on backbone hardware you have no control over.

Even Linux struggles with this, to the point where you need to do some configuration for high-bandwidth networks (eg RPS [3]). Just handling all those interrupts presents a bunch of problems beyond the original scope. And again, it's hard to fix through no fault of Linux's.

I'm old enough to remember the talk about us running out of IPv4 addresses back in the 1990s. It's been interesting to watch how this has consistently been kicked down the street (eg cgNAT).

What is funny though is large companies (eg Facebook) actualy ran out of internal addresses on a 10/8 network and there's no good solution for that (with IPv4 at least).

[1] https://en.wikipedia.org/wiki/Second-system_effect

[2] https://en.wikipedia.org/wiki/Robustness_principle

[3] https://lwn.net/Articles/362339/

jcgl7• 4 months ago

3. History has shown that upgrading network backbone hardware (in particular) is incredibly difficult through a process that's been described as "ossification", which is a nice description. Basically, network relays and routers wanted to avoid security issues and decided to discard things they didn't understand.

What makes you suggest that it's backbone hardware that is the problem? It's largely enterprise customers and tier 3 providers that don't really do IPv6 afaics.

Hikikomori6• 4 months ago

3. History has shown that upgrading network backbone hardware (in particular) is incredibly difficult through a process that's been described as "ossification", which is a nice description. Basically, network relays and routers wanted to avoid security issues and decided to discard things they didn't understand.

Would say the opposite is true. Core routers were the first to enable V6 support in any network as they would need support it for anything else to even use it. They got regularly replaced as bandwidth needs keeps rising as well.

Plenty of isps advertise ipv6 but haven't managed to give it to customers yet.

Interrupts are hardly a problem with any nics of the last decade really.

Companies like Facebook can and do use 240/4.

Yizahi2• 4 months ago

I honestly don't understand why IPv6 is not actively deployed in 2026. Every piece of networking hardware over past decade supports IPv6 and often dual stack too. And to switch between both often takes a few clicks if DHCPv6 server is up and reachable. Absolutely transparent, free, zero performance hit. But no, so many persist at doing v4.

PS: I'm talking about MSO hardware. But client hardware should be at the same level of compatibility for years too.

thomasdziedzic2• 4 months ago

2026:

  $ ping6 github.com
  ping6: github.com: Address family for hostname not supported

Yizahi2• 4 months ago

Yeah, that's the problem. And I bet they could enable it, they just don't want to for some reason.

Hikikomori6• 4 months ago

Azure has very poor V6 support last I tried it.

commandersaki4• 4 months ago

Support nightmare for ISPs.

gmuslera• 4 months ago

It is the only way forward, but the reason for that is not the correlation between population and IP addresses. After all, most of the use of internet today is not by people, but by bots, crawlers, AI agents, b2b and more, and that is far more than the human population, and then you have the virtual networks built over IP like VPNs, Tor and more. It is more related to privacy, bidirectional communication and protocols, security, identity and possibilities.

Bender6• 4 months ago

The only place I have utilized an IPv6 address publicly is on my authoritative name servers only because some DNS testing tools assume it is there. It's not really needed however. My home firewall does have one but I have never used it. I can't think of a use for it. I have multiple static IPv4 addresses and they have suited me just fine for decades. I suppose I could bind a Squid SSL Bump MitM proxy to it in case a site blocks me but I would probably leave it off most of the time.

I never use them on my web, chat, voice, IRC and other servers as I personally find blocking shenanigans on IPv4 and not having to implement the same checks on IPv6 is just easier for a lazy person like me. IPv6 just feels like an after-thought bolt on to me. Clunky, not well thought out. Some privacy gotchas that can be disabled but some will not. That's just my take. I doubt anyone will have the same take.

I think IPv4 will be fine for another 100 years even if we have to re-purpose some DoD/MoD ranges given they don't use them and maybe annex some /8's from a few greedy companies. But that's a problem for Gen Delta. Gen Foxtrot can deal with repurposing some multicast ranges.

kalleboo5• 4 months ago

I have multiple static IPv4 addresses and they have suited me just fine for decades

IPv6 is for the people (countries, continents) who did not get in early on the IPv4 address gold rush. Your take is basically "got mine, F you".

Bender6• 4 months ago

Or ... people can use the DoD/Mod and assorted other space to get their IPv4 allocations. There is a ton of unused space in IPv4. Reserved, allocated but entirely unused. Also take back some /8's from greedy companies that don't need all that space. stares at HP When I say take I mean take as in a forceful annex and a timeline.

flumpcakes• 4 months ago

One of the biggest, I would assume in the current year, blockers to an IPv6 only world would be the fact that the major "cloud" vendors do not support it.

bombcar2• 4 months ago

The companies that rent you IPv4 addresses don’t support v6 well or at all? Do tell. I wonder why.

matttttttttttt• 3 months ago

AWS supports IPv6 and it's free, whereas IPv4 is not.

lern_too_spel3• 4 months ago

https://isgithubipv6.live/

tsoukase5• 4 months ago

If IPv6 doesn't dominate in the next, let's say, 10 years, they might publish the IPv8 which will be an 64bit space, backwards compatible with IPv4. It will be the only case where a newer version of software comes back closer to an older one.

p1mrx2• 4 months ago

the only case where a newer version of software comes back closer to an older one

Winamp 3 -> Winamp 5 was closer to Winamp 2. Windows 8 -> Windows 10 was closer to Windows 7.

Though I don't expect this to happen with IP.

BenjiWiebe8• 4 months ago

How do you plan to let IPv4 (32 bit address space) actually address and communicate with an IPv8 (64 bit address space) host? You don't have enough bits to identify the v8 host.

tsoukase5• 3 months ago

Something like 1:2:3:4:a:b:c:d where the most significant 32bits are a valid IPv4. The kernel figures out and keep all others the same (NAT etc). We extend the address space, not invent a new stack. The IPv6 critics shout out that this would be a viable solution.

journal• 4 months ago

Will IPV6 become a type in sql databases?

landgenoot• 4 months ago

The INET6 data type is intended for storage of IPv6 addresses, as well as IPv4 addresses assuming conventional mapping of IPv4 addresses into IPv6 addresses.

throw0101d13• 4 months ago

Will IPV6 become a type in sql databases?

Both IPv4 and IPv6 addresses are 'just' u_ints: one is 2^32 and the other is 2^128. The fact that we display them in a particular format (10.11.12.13; ff:ee::bb:aa) is only for human UX purposes.

Strictly speaking everything in a computer is 'just' a number represented in base-2 (binary digits: bits) that we affix certain labels to (char, int, float, struct).

rickcarlino• 4 months ago

Imagine being able to connect two computers over the internet using sockets. WebRTC is a marvel, but I miss the whimsical days of running something on a port at home and connecting to it without thinking about NAT.

kalleboo5• 4 months ago

Imagine being able to make a voice call to a friend without paying for a middle-man to proxy the traffic completely unnecessarily.

vsgherzi• 3 months ago

You can still do this! It’s just very hard and needs hole punching and maybe a stun server

sidcool• 4 months ago

What dictates the allocation per country?

orangeboats14• 4 months ago

IPv4 - first come first served, with a 24 karat FU to the 3rd world countries. It is their fault that they are poor.

IPv6 - still the same, but the space is large enough that any first-mover advantage is minuscule.

labcomputer5• 4 months ago

I think that's a bit uncharitable.

32 bits seemed practically infinite at the time IPv4 was created, and the whole thing started as a way for the American military-industrial-research complex to communicate with itself anyway. Why would you even want to assign addresses on your defense network to foreign adversaries?

Now that it's a commercial thing, a more equitable distribution would have, with hindsight, been a good thing.

rkagerer3• 4 months ago

The main complaint I have against IPv6 is the addresses are so unwieldy. When I look at them I have the same reaction as when I look at some kind of complex scientific formula comprised of operators and symbols that are unfamiliar. It also takes extra mental effort to expand the compressed zeros and interpret what I'm viewing.

Even after reading about them many times and using them in (an albeit limited) fashion, they still just don't feel human friendly. Not like the more straightforward IPv4 addresses do. (Or even like a hypothetical "IPv5" that simply prefixes one extra octet).

Whenever I bring this up I'm told something like "Don't bother memorizing IPv6 addresses. Use DNS instead."[1]

That take completely overlooks the fact that if the numbers exist, you will inevitably wind up needing to deal with them at various points along the way. Eg. Debugging logs, sniffing network traffic, ruling out if DNS is down, etc. I'm a big fan of ergonomics to make things intuitive and reduce unnccessary cognitive overhead, and the new scheme is a regression in that regard.

If anyone has tips on how they became more fluent with IPv6 I'd love to hear.

[1] https://www.networkworld.com/article/934784/mission-impossib...

rkagerer3• 4 months ago

This is without even getting into learning the new (old?) paradigm of "exposing" all addresses to the whole internet. I realize "NAT" is not equivalent to "firewall", but placing them at the same boundary made things simple to understand conceptually. I for one never had trouble opening/forwarding ports (and liked the control it provided over what goes in and out, especially in the days before it all just became HTTP) but I sympathize with the major headaches the NAT "workaround" caused.

lunar_rover• 4 months ago

NAT also solves the dynamic address issue. With GUA I need to deal with both dynamic prefix and randomised suffix that can be changed by seemingly unrelated things when opening ports to the internet.

Dagger218• 4 months ago

Just use it. This reaction is coming from a lack of familiarity, not from it actually being hard.

Here's some roughly equivalent IP addresses:

    203.0.113.45+192.168.1.1 ↔ 2001:db8:2d4f:1::1
    203.0.113.45+192.168.1.2 ↔ 2001:db8:2d4f:1::2
    203.0.113.45+192.168.1.3 ↔ 2001:db8:2d4f:1::3
    203.0.113.45+192.168.2.1 ↔ 2001:db8:2d4f:2::1

The v6 addresses are made up of the network prefix (2001:db8:2d4f, basically an opaque string like 203.0.113.45+192.168), then the subnet ID (1, 2) and then the host ID on the network (1-3 and 1).

When you look at 2001:db8:2d4f:X::Y, it should be pretty easy to see that it's host Y on subnet X, under your prefix which is the same for your whole network. Even if it's 2001:db8:2d4f:X:YYYY:YYYY:YYYY:YYYY it's still the same thing, just with more characters.

rkagerer3• 4 months ago

Thanks, that's a helpful comparison. You've shown a fixed prefix 3 hextets (48 bits) in length - is that the most common convention these days?

And has the practice of generating portions of the address from your MAC address been universally (or at least mostly) abandoned?

preisschild2• 4 months ago

I love IPv6, SLAAC, mDNS, Thread, Matter and the other cool stuff in the ecosystem. I have wasted too much time setting manual DHCP static assignments. Now I just use SLAAC and mDNS with basically no manual config.

nesarkvechnep• 4 months ago

Reading the comments, it looks like some people dismiss IPv6 just because they need to sit down and learn a couple of new things.

MaKey2• 4 months ago

Yeah, it's always the same with IPv6 discussions. The main points being:

  1. IPv6 addresses are too long to remember
  2. IPv6 doesn't need NAT and people are uncomfortable with their devices having a public address as they see NAT as an additional layer of security

redserk• 4 months ago

If someone is still using the “remembering IP addresses” argument in 2026 (or at any point in the 21st century), I question their technical competence in configuring a network correctly.

wao0uuno2• 4 months ago

I dismiss IPv6 because my ISP doesn't support it.

voxadam• 4 months ago

I dismiss ISPs that don't support IPv6.

bdeol22• 4 months ago

We've had enough address space for ages—the recurring pain is incentives at org boundaries: whoever owns the legacy peerings pays the migration tax.

everdrive• 4 months ago

Here comes the flood of IPv6 evangelists who thinks everyone is confused about NAT and firewalls. I don't know where they get their talking points, but they descend onto these threads with their sanctimony. "Oh, you must be confused about how NAT works, allow me to educate you." It's very tiresome.

artooro• 4 months ago

I'm surprised how few people are talking about ULAs. For any home network where you don't have a reserved global address space from your ISP, it makes sense to configure a ULA on your router and use it for all internal hosts, and the ISP assigned address is only used for Internet access. This does not require NAT/Npt and you have the best of both worlds.

skybrian• 4 months ago

First I heard of it. Apparently they are private Ipv6 addresses:

https://en.wikipedia.org/wiki/Unique_local_address

If your intranet has no IPv4 addresses, this is better than a NAT somehow?

fulafel5• 4 months ago

If you want to have an airgapped network, sure. For most people it doesn't make sense. You'll just get the worst of of both worlds.

kstrauser7• 4 months ago

It’s pretty sweet. By using ULA addresses for everything, all internal networking keeps working as-is if my ISP allocation changes. Every host can talk to its neighbors using internal addresses, and still connect to remote hosts without NAT breakage.

esbranson4• 4 months ago

RFC 7368 for home networks recommends the use of ULA locally.

A home network running IPv6 should deploy ULAs alongside its globally unique prefix(es) to allow stable communication between devices (on different subnets) within the homenet
When an IPv6 node in a homenet has both a ULA and a globally unique IPv6 address, it should only use its ULA address internally and use its additional globally unique IPv6 address as a source address for external communications.

eqvinox• 4 months ago

You're supposed to use them in parallel, not as an alternative.

illiac7863• 4 months ago

There are ISPs out there that distribute IPv6 to the WAN intf of the home router without a /64? What’s the point for them?

esbranson4• 4 months ago

Unmentioned in the Wikipedia article is RFC 7368 IPv6 Home Networking Architecture Principles[1] that discusses them as well.

A home network running IPv6 should deploy ULAs alongside its globally unique prefix(es) to allow stable communication between devices (on different subnets) within the homenet

[1] https://datatracker.ietf.org/doc/html/rfc7368.html#section-2...

soupbowl• 3 months ago

I use ULAs since my ISP changed my ipv6 prefix twice a month. What I learned is that ipv6 configuration usually requires a more 'comerical grade' router. In the end it works well for me but getting it setup initially took a lot of effort. Easy to do the second time though.

I later moved and my current ISP does not have ipv6 support but my ULA setup kept working fine with some minor tweaks.

gosub1002• 4 months ago

Can someone pity me enough to explain how to do DNS on ipv6 while using slaac?

All I want to do is give every machine on my network a friendly hostname like storage.lan, timsPhone.lan, etc without having to run BIND (if possible), or dhcpd.

I have heard of zeroconf for ipv4, but the catch is I want this to work across several different platforms like Windows , freebsd, Linux, etc. I also don't want to use static addresses, but I feel like that's asking too much.

WorldMaker4• 4 months ago

You are looking for mDNS which is the modern name for zeroconf/Bonjour/etc. The URL suffix is .local (storage.local, myphone.local, myprinter.local). Most modern OSes support it out of the box, but also don't advertise their names on mDNS until you ask them nicely (travel through a maze of Settings and Firewall options).

mDNS supports IPv6 just fine/works on IPv6 only LANs.

https://en.wikipedia.org/wiki/Multicast_DNS

gosub1002• 4 months ago

Thank you. I may have tried this previously, but I think my router was blocking traffic between WiFi and wired. I will try this again. Appreciate it

ebiederm• 4 months ago

For everyone getting into the details about how all of this should work please look at RFC7084: Basic Requirements for IPv6 Customer Edge Routers

https://www.rfc-editor.org/rfc/rfc7084

It describes in detail what a home router needs to be doing to make all of this work seamlessly.

Things work so well that half the world has working IPv6 already.

Openwrt pretty much implements all of this out of the box.

If you are struggling with IPv6 I recommend reading up on where it is at today and figuring out how whatever makes your network special can be done using IPv6 with no fuss.

Personally I have moved several times changing ISPs in the process and my IPv6 setup involving multiple LANs on my home network has just continued to work. IPv6 renumbering events just work seamlessly and completely automatically.

Historically the only practical hold up to IPv6 adoption has been the ISPs not rolling it out to their customers.

esbranson4• 4 months ago

And I know the homenet WG has concluded but I found RFC 7368 IPv6 Home Networking Architecture Principles[1] interesting as well, including its discussion of reachability and RFC 6092 Recommended Simple Security Capabilities in Customer Premises Equipment (CPE) for Providing Residential IPv6 Internet Service.[2] IPv6 still occasionally seem more flaky than IPv4 with some set ups though.

[1] https://datatracker.ietf.org/doc/html/rfc7368.html#section-3...

[2] https://datatracker.ietf.org/doc/html/rfc6092

throw0101d13• 4 months ago

Historically the only practical hold up to IPv6 adoption has been the ISPs not rolling it out to their customers.

And corporate networks: in Google's stats you'll see IPv6 usage jumps on weekends as people do stuff not using their work computer.

lee_ars2• 4 months ago

If you are struggling with IPv6 I recommend reading up on where it is at today and figuring out how whatever makes your network special can be done using IPv6 with no fuss.
...
Historically the only practical hold up to IPv6 adoption has been the ISPs not rolling it out to their customers.

Yep, that's where I am. Frontier FTTH, IPv4 only. Because....I have no idea why. Because Frontier sucks, basically? They have at least started their rollout:

https://stats.labs.apnic.net/ipv6/AS5650?c=US&p=1&v=1&w=30&x...

...but it's going to be slow going. Don't get me wrong, I'd rather cut off my fingers than go back to Comcast, but at least Comcast gave me a /56.

anikom152• 4 months ago

NAT is good enough.

ottah• 3 months ago

Ipv6 is a theoretical benefit to the commons but as an individual it's an increase in complexity and a new abstraction for nearly the same result as your existing ipv4 network. There's just not enough incentive to invest in the switch.

cybercatgurrl• 3 months ago

The same annoying and trite IPv6 haters come out of the woodworks with every article posted.

IPv6 is the only way forward

Related Stories