Basically what the title says. Here’s the thing: address exhaustion is a solved problem. NAT already took care of this via RFC 1631. While initially presented as a temporary fix, anyone who thinks it’s going anywhere at this point is simply wrong. Something might replace IPv4 as the default at some point, but it’s not going to be IPv6.
And then there are the downsides of IPv6:
- Not all legacy equipment likes IPv6. Yes, there’s a lot of it out there.
- “Nobody” remembers an IPv6 address. I know my IPv4 address, and I’m sure many others do too. Do you know your IPv6 address, though?
- Everything already supports IPv4
- For IPv6 to fully replace IPv4, practically everything needs to move over. De facto standards don’t change very easily. There’s a reason why QWERTY keyboards, ASCII character tables, and E-mail are still around, despite alternatives technically being “better”.
- Dealing with dual network stacks in the interim is annoying.
Sure, IPv6 is nice and all. But as an addition rather than as a replacement. I’ve disabled it by default for the past 10 years, as it tends to clutter up my ifconfig overview, and I’ve had no ill effects.
Source: Network engineer.
Why would I need to remember an ip address if I have a hostname? I don’t know my ipv4 anywhere since it’s all dynamic.
Standards like those change just fine. Sure some stuff uses ascii still, but almost everything I encounter is unicode. Email has had so many things added on over the years that that’s not a fair comparison either. Other countries have plenty of kb layouts that are more popular locally than qwerty but came afterwards.
At some point ipv6 will be the default and we’ll just use compatibility layers to access ipv4 only things. We don’t need every device on board, just the ISPs
Thank you.
I’ve said this repeatedly in many communities and it’s like I killed the golden goose - people lose their minds.
I disable IP6 everywhere - my router NATs everything as it is, why have another protocol running if I don’t use it?
We’ll see what the future brings.
I’d be somewhat lenient when it comes to IPv6 if it used 64 bit addresses instead of 128bit. It would still not be needed thanks to NAT, CIDR and DHCP, but at least a 64bit address space is more manageable.
It’s great for backbone and public address space - and maybe in enterprise, but there it’s a costly transition that won’t happen immediately. Things will change as hardware ages out and is replaced.
New infrastructure will be mostly IP6.
And when people leave the office, their machines will connect to, and transit IP4 networks, so they’ll still need to address how everything works over IP4 (say VPN connections, any hardware/software that’s still IP4 dependent in the data centers, etc).
So then this is actually a popular opinion? ;)
More popular than I anticipated, but at least somewhat controversial based on the vote ratio.
Which is hilarious because you hit the nail on the head. IPV6 is not new, it would have long ago been adopted if ever it were gonna. Who is still holding out hope….and why? lol
Only real world advantage of IPv6:
::1 vs 127.0.0.1
Please tell me there’s something similar for 192.168.0.1
I’m a web developer and I’ve never once used an IPv6 address for any circumstance. My ISP doesn’t use IPv6 either in my region (Starlink).
IPv6 should be available for you to use on starlink. You may need to set up your router to use it.
I’m a web developer and I’ve had to ensure both work properly as users across the globe usually have one or the other or both.
It might be time to do some good by your users and implement it (or better yet 20 years ago).
I’ve got Starlink and IPv6 works fine. That’s the only way I can host anything since IPv4 is CGNAT. You have to use your own router for IPv6 since theirs is a piece of junk.
My cell carrier is T-mobile and it’s IPv6 only. They do have some sort of translator for accessing legacy sites though.
While the hype is less these days, theres more and more thats connected with ipv6. While I do t use it in my home-lab, theres advantages besides nat.
You dont need ipv4 for intent based networking/firewalls, and I guess as a network engineer you know this is the new buzzword for selling equipment.
Source: I pay nerwork engineers and architects
43% of Google traffic is now ipv6 and steadily growing
https://www.google.com/intl/en/ipv6/statistics.html
CGNAT is only a temporary band aid for reaching services that are yet to present themselves on IPV6. It’s relatively expensive to operate.
IpV6 might be largely pointless on a LAN, and sure NAT is fine there, but ipv6 already running large chunks of the world’s mobile infrastructure. It’s not going anywhere.
Is this one of those cases where it takes 20 years for equipment to turn over, so why not just do it?
It’s like any new car requirement, it takes 20+ years for the car fleet to turn over, but it’s worth it.
IPv6 was introduced 26 years ago, so it will have to be longer than that
That’s a very literal read of the concept I was trying to put forward.
I have a decently-sized homelab, and a large home network. I also have IPv6 disabled everywhere. Compared to a normal home network, my config is very complex. (Extensive firewall and routing rules, multiple gateways, multiple subnets and VLANs, inbound traffic filtering, and plenty more.) With the exception of VLANs, IPv6 would require reconfigurijg EVERYTHING. What’s the advantage?
Bingo!
Now consider a large business with dozens or hundreds of network devices.
Uggh, the chsllenges.
New infra will likely have IP6 enabled, and they’ll slowly switch.
it’s been the default for my smartphone for years. (t-mobile)
AFAIK, IPv6 does not truely address the router memory concern. With so many more addresses and more space-per-address in the tables, i imagine it’s only a matter of time till we are back to such fundamental woes as “where does this packet go”… but i suppose that is limited by the rate that people buy and move ipv6 address blocks.
You say that something may replace IP4, but it won’t be IP6, then you list a lot of reasons why it can’t be IP6, except all those reasons would apply to whatever that something is also.
Upvote for semi-unpopular opinion.
I think you’re wrong about the shortage being ‘solved’ by NAT. NAT is great for LAN and WAN in the developed world, but there are billions of folks in remote developing areas where it’s not much help. It also severely limits the big chunks of address spaces that can be allocated to business, universities, governments, etc. It is not a trivial problem waved away by NAT.
I think it will continue to be a very gradual but relentless rollout of IPv6. Not saying it will be fast. But 30 years from now, if we haven’t destroyed civilization, I suspect IPv4 will be a quaint relic. And IPv6 will never run out of addresses.
There’s a large possibility we’ll run out of IPv6 addresses sooner than we think.
Theoretically, 128-bits should be enough for anything. IPv6 can theoretically give 2^52 IPs to every star in the universe: that would be a 76-bit subnet for each star rather than the required 64 minimum. Today, we (like ARIN) do 32-48-bit allocations for IPv6.
With IPv4, we did 8-24-bit allocations. IPv6 gives only 24 extra allocation bits, which may last longer than IPv4. We basically filled up IPv4’s 24-bits of allocations in 30 years. 281 trillion (2^48) allocations is fairly reachable. There doesn’t seem to be any slowdown of Internet nor IP growth. Docker and similar are creating more reasons to allocate IPs (per container). We’re also still in the early years of interstellar communications. With IPv4, we could adopt classless subnetting early to delay the problem. IPv6’s slow adoption probably makes a similar shift in subnetting unlikely.
If we continue the current allocation trend, can we run out of the 281 trillion allocations in 30 years? Optimistically, including interstellar networks and continued exponential growth in IP-connected devices? Yes. Realistically, it’s probably more than 100 years away, maybe outside our lifetimes, but that still sounds low when IPv6 has enough IPs for assigning an IP to every blade of grass, given every visible star has an Earth. We’re basically allocating a 32-48 bit subnet to every group of grass, and there are not really enough addresses for that.
This is the worst math that ever mathed. IPv4 is 32 bits of address space. IPv6 is 128. That is 2^32 vs 2^128. Not 2^52, which isn’t even wrong it’s just weird, hopefully this is just some weird performance joke. There are enough addresses in ipv6 to address every known atom on earth. We aren’t running out anytime soon. 96 doublings of IPv4s address space is a number you can’t fathom.
That wasn’t what I said. 2^56 was NOT a reference to bits, but to how many IPs we could assign every visible star, if it weren’t for subnet limitations. IPv6 isn’t classless like IPv4. There will be a lot of wasted/unrunused/unroutable addresses due to the reserved 64-bits.
The problem isn’t the number of addresses, but the number of allocations. Our smallest allocation, today, for a 128-bit address: is only 48-bits. Allocation-wise, we effectively only have 48-bits of allocations, not 128. To run out like with IPv6 , we only need to assign 48-bits of networks, rather than the 24-bits for IPv4. Go read up on how ARIN/RIPE/APNIC allocate IPs. It’s pretty wasteful.
I’m fully aware how rirs allocate ipv6. The smallest allocation is a /64, that’s 65535 /64’s. There are 2^32 /32’s available, and a /20 is the minimum allocatable now. These aren’t /8’s from IPv4, let’s look at it from a /56, there are 10^16 /56 networks, roughly 17 million times more network ranges than IPv4 addresses.
/48s are basically pop level allocations, few end users will be getting them. In fact comcast which used to give me /48s is down to /60 now.
I’ll repeat, we aren’t running out any time soon, even with default allocations in the /3 currently existing for ipv6.
I’m fully aware how rirs allocate ipv6.
Sorry, but your reply suggests otherwise.
The RIRs (currently) never allocate a /64 nor a /58. /48 is their (currently) smallest allocation. For example, of the ~800,000 /32’s ARIN has, only ~47k are “fragmented” (smaller than /32) and <4,000 are /48s. If /32s were the average, we’d be fine, but in our infinite wisdom, we assign larger subnets (like Comcast’s 2601::/20 and 2603:2000::/20).
These aren’t /8’s from IPv4. let’s look at it from a /56, there are 10^16 /56 networks, roughly 17 million times more network ranges than IPv4 addresses.
Taking into account the RIPE allocations, noted above, the closer equivalent to /8 is the 1.048M /20s available. Yes, it’s more than the 8-bit class-A blocks, but does 1 million really sound like the scale you were talking about? “enough addresses in ipv6 to address every known atom on earth”
The situation for /48s is better, but still not as significant as one would think. With Cloudflare as an extreme example: They have 6639 IPv4 /24 blocks, but 670,550 IPv4 /48 blocks. Same number of networks in theory, but growing from needing 13-bits of networks in IPv4 to 19-bits of networks: 5 extra bits of usage from just availability.
That sort of increase of networks is likely-- especially in high-density data centers where one server is likely to have multiple IPv6 networks assigned to it. What do you think the assignments will look like as we expand to extra-terrestrial objects like satellites, moons, planets, and other spacecraft?
I’ll repeat, we aren’t running out any time soon
Soon vs never. OP I replied to said “never”. Your post implied similarly, too-- that these numbers are far too big for humans to imagine or ever reach. The IPv6 address space is large enough for that: yes. But our allocations still aren’t. The number of bits we’re actually allocating (which is the metric used for running out) is significantly smaller than most think. In the post above, you’re suggesting 56-64 bits, but the reality is currently 20-32 bits-- 1M-4B allocations.
If everyone keeps treating IPv6 as infinite, the current allocation sizes would take longer than IPv4 to run out, but it isn’t really an unfathomable number like the number of atoms on Earth. 281T /48s works more sanely: likely enough for our planet-- but RIPEs seem to avoid allocating subnets that small.
IPv4-style policy shifts could happen: requirements for address blocks rise, allocation sizes shrink, older holders have /20 blocks (instead of 8-bit class A blocks), and newer organizations limited to /48 blocks or smaller with proper justification. The longer we keep giving away /20s and /32s like candy, the more likely we’ll see the allocations run out sooner (especially compared to never). My initial message tried to imply that it depends on how fast we grow and achieve network growth goals:
30 years? Optimistically, including interstellar networks and continued exponential growth in IP-connected devices? Yes.
. . .
Realistically, it’s probably more than 100 years away, maybe outside our lifetimes
Sorry, but your reply suggests otherwise.
I’m at work, I’m not going to go into a thesis on ip allocation.
The RIRs (currently) never allocate a /64 nor a /58. /48 is their (currently) smallest allocation. For example, of the ~800,000 /32’s ARIN has, only ~47k are “fragmented” (smaller than /32) and <4,000 are /48s. If /32s were the average, we’d be fine, but in our infinite wisdom, we assign larger subnets (like Comcast’s 2601::/20 and 2603:2000::/20).
Correct all noted here https://www.iana.org/numbers/allocations/arin/asn/
Taking into account the RIPE allocations, noted above, the closer equivalent to /8 is the 1.048M /20s available. Yes, it’s more than the 8-bit class-A blocks, but does 1 million really sound like the scale you were talking about? “enough addresses in ipv6 to address every known atom on earth”
If you’re going to go through and conflate 2^128 as being larger than the amount of atoms on earth to a prefixing assignment scheme I’m just going to assume this is a bad faith argument.
Have a good one I’m not wasting more time on this. The best projections for “exhausting” our ipv6 allocations is around 10 million years from now. I think by then we can change the default cidr allocations.
https://samsclass.info/ipv6/exhaustion-2016.htm
Its old sure but not worth arguing further.
There’s been only one real purpose of v6 that I’ve seen being the reason to switch: v4 running out of available addresses. Never seen anything else about v6 being used as any kind of reason to switch. So the only reason we’d ever go over to v6 is because we have to, not because we want to.
This whole debate is so tired. Just use IPv6, it’s 2024 and it’s so fucking easy these days.
