12 ms·

As someone who grew up on IPv4, i will miss it, but the leap to 340 undecillion unique addresses is exciting in many ways so i think i can learn to live with th

As someone who grew up on IPv4, i will miss it, but the leap to 340 undecillion unique addresses is exciting in many ways so i think i can learn to live with this transition. If we ever need more than that, i can't even imagine what that future would look like.

p-e-w 3y ago
The last time I looked into this (which was a few years ago), ISPs were allocating blocks containing billions of IPv6 addresses to anyone who paid a nominal sum. So that vast address space might not last as long as it would seem...
- internetter 3y ago
  We never learn
- greyface- 3y ago
  That sure sounds like a lot. But "billions" is less than a /64. Try "sextillions" (/56) or "septillions" (/48). Of course, when the denominator is "undecillions", it becomes clear that this is actually a non-issue.
  - joering2 3y ago
    I'd even go out of my way and say that undecillion of IP addresses ought to be enough for anybody.
    - dns_snek 3y ago
      Bold prediction! Let's see if it holds true in 200 years when every cybernetic cell in your body is individually addressable from the public internet.
      - ale42 3y ago
        This is almost IPv9 (RFC1606)! https://datatracker.ietf.org/doc/html/rfc1606 https://datatracker.ietf.org/doc/html/rfc1606 The up to 42 deep hierarchy of routing levels built into IPv9 must have been one of the key features for its wide deployment. [...] As yet, no requirement has been found for levels 40-42, with level 39 still being used for experimental interrogation of atomic structure of components where required. Of course, it's a 1st April RFC. For those who don't know them, see https://en.wikipedia.org/wiki/April_Fools'_Day_Request_for_Comments https://en.wikipedia.org/wiki/April_Fools'_Day_Request_for_C...: they include thinks like terminals with subliminal messages, IP over pigeons...
      - Nition 3y ago
        98% of all IPv6 addresses will be set aside for self-replicating nanobots and our bodily cells will have to fight over only the remaining 2%.
  - mike_d 3y ago
    ARIN recently handed out a /16 allocation to Capital One. That is one 65,025th of all of IPv6. A reasonable sized /32 allocation would have allowed for giving every ATM they operate worldwide its own globally routable /48.
    - greyface- 3y ago
      Too bad ARIN tickets aren't public - I would love to read the one in which that was justified. Reading NRPM 6.5.2.1, it seems that they must have submitted documentation claiming at least 2^28 distinct serving sites in order to qualify for an assignment that large.
    - ta1243 3y ago
      I find the insistence of using /64s everywhere for networks frustrating. Any network larger than a /112 seems crazy, that's already 65k IPs per subnet. A /104 for every normal end user (256 subnets per user), or a /80 for massive companies like Capital One (4 billion subnets) should be more than enough.
      - tuetuopay 3y ago
        There is a really practical reason behind this, and it is called "routers". Due to longest prefix match, you'll end up wasting resources on the networking hardware. And you waste both precious and expensive TCAM and LPM latency for matching the prefixes. So routers do optimize for anything shorter than /64, and have special lookup memory for /64 and /128. But nothing in-between.
        ta1243 3y ago
        That's fair enough, in which case ipv6 is really only a /76 (having more than 1000 hosts on a subnet isn't a great thing, even with no broadcast and arp and other traffic, and /76 allows 4000 on a /64) Those fanboys going "we'll never run out of 2^128 IPs" are being disingenuous when about 2^59 of them have been burnt straight away (I'd guess most subnets have less than 30 devices) 2^64 subnets is a reasonable number, but when they are handed out like candy that number dwindles quickly. ARIN is allocating the equivalent of a /15 every year. That's fine if it's a constant allocation, there's 100,000 years worth, but if that rate grows, the space will be eaten in a matter of a few decades.
  - iLoveOncall 3y ago
    I'm sure people said exactly this about IPv4 back in the days.
    - dns_snek 3y ago
      Can you even begin to imagine a use case that could come close to exhausting an IP space that is perfectly capable of assigning a /60 subnet to every single grain of sand on earth? That subnet is large enough to then assign an IP address to every individual atom in that grain of sand. For comparison, if we wanted to assign every living person on Earth a grain of sand, we would only need a few cubic feet of it (less than 1 cubic meter).
      - corobo 3y ago
        Nanites might give you a good start Of course we'd all be paperclips long before they need to worry about networking
      - diggan 3y ago
        > Can you even begin to imagine a use case that could come close to exhausting an IP space that is perfectly capable of assigning a /60 subnet to every single grain of sand on earth? As parent said, I'm sure people made the exact same argument about IPv4 back in the day, but comparing it to something else. And when IPv16 finally appears in the future, people will yet again make exactly the same argument.
        dns_snek 3y ago
        > As parent said, I'm sure people made the exact same argument about IPv4 back in the day, but comparing it to something else. You're ignoring the sheer scale of this question. We don't have enough raw materials on this planet, or likely in the observable universe, to produce enough devices that would consume that many IPs. We could colonize 1 billion planets. Each of those planets could have 100 billion people. Each of those 100 billion people could own 1 billion "things" that could be considered "networked devices". Each of those "things" could consume 1 billion IPs. We could have all that, and we would still have 70% of the IPv6 space left. > The decision to put a 32-bit address space on there was the result of a year’s battle among a bunch of engineers who couldn’t make up their minds about 32, 128 or variable length. And after a year of fighting I said — I’m now at ARPA, I’m running the program, I’m paying for this stuff and using American tax dollars — and I wanted some progress because we didn’t know if this is going to work. So I said 32 bits, it is enough for an experiment, it is 4.3 billion terminations — even the defense department doesn’t need 4.3 billion of anything and it couldn’t afford to buy 4.3 billion edge devices to do a test anyway. So at the time I thought we were doing a experiment to prove the technology and that if it worked we’d have an opportunity to do a production version of it. Well — [laughter] — it just escaped! — it got out and people started to use it and then it became a commercial thing. - https://www.youtube.com/watch?v=mZo69JQoLb8&t=816s https://www.youtube.com/watch?v=mZo69JQoLb8&t=816s They were contemplating 128 bits addresses all the way back then, but settled on 32 bits as a mere proof of concept that got out of hand.
- pilif 3y ago
  One of the features of IPv6 is address autoconfiguration, obviating the need for a central authority like DHCP on v4. However, that only works with a /64 prefix and given that larger sites might want to have multiple subnets, that’s why most assignments are /56 or /48. But still. If all assignments were /48s, that would still leave room for 281 trillion networks which even I believe is enough for the foreseeable future. If the number space is so big, it makes sense to take advantage of it if that allows for other additional features (like SLAAC)
  - londons_explore 3y ago
    > However, that only works with a /64 prefix Well it should be redesigned so it works all the way down to individual addresses.
    - greyface- 3y ago
      You can use DHCPv6 instead of SLAAC if you need autoconfiguration on sub-/64 prefixes.
      - scheme271 3y ago
        Some systems like android don't support anything but SLAAC
        ale42 3y ago
        IMHO it means that they are not fully IPv6 compliant. Corporate networks often have DHCPv6 rather than just SLAAC.
        bert64 3y ago
        They are fully compliant, SLAAC is part of the standard whereas DHCPv6 is an optional extra. DHCPv6 also does not work without RA. DHCPv6 just assigns an address, a routable prefix, dns servers etc, it does not assign a subnet or any routes, you need route advertisements for that.
- Kab1r 3y ago
  Billions of addresses might seem like a lot, but every IPv6 network has at least 2^64 addresses and it doesn't make much sense (to me) to give any customer less than one network. (Maybe you meant billions of /64 blocks? ISPs could be providing a /32 ≈ 4 billion /64 blocks, though there still are 2 billion of those in the entire IPv6 space)
- porbelm 3y ago
  ISPs are SUPPOSED to allocate a /64 for a single customer. Mine does, so I have 4.5 billion available addresses within my 2001:4653:nnnn:nnnn::/64 prefix...
  - ptman 3y ago
    2^32 is ~4.3*10^9 2^64 = 2^32 * 2^32 , so quite a bit more
  - cesarb 3y ago
    > ISPs are SUPPOSED to allocate a /64 for a single customer. Weren't they supposed to allocate a /48? Or did that change while I wasn't looking?
    - greyface- 3y ago
      > Or did that change while I wasn't looking? Yes: https://datatracker.ietf.org/doc/html/rfc6177 https://datatracker.ietf.org/doc/html/rfc6177
- throw0101d 3y ago
  > So that vast address space might not last as long as it would seem... Have you done the math? * math property: x^y = x^(a+b) = (x^a )x(x^b ) * IPv4 addresses are 32 bits (2^32 ) * 2^32 ~ 4.3 billion * So the IPv4 Internet has ~4.3B devices on it * IPv6 subnets are 64 bits, /64 (2^64 ) So, a IPv6 2^64 subnet is the same as (2^32 )x(2^32 ), which means (4.3B)x(IPv4 Internet). I.e., a single IPv6 subnet can hold the equivalent of four billion (IPv4) Internets. A second way of thinking about it: * Stars in the Milky Way: 400 Billion * Galaxies in the universe: 2 Trillion So (4x10^11 )x(2x10^12 )=8x10^23 stars in the universe. * Size of IPv6 address space: 3.4x10^38 Find the ratio between addresses and stars: * 3.4x10^38 / 8x10^23 IPv6 offers about 430 trillion times more addresses than estimated stars in the universe. A third way: On the surface of the Earth (land+water), there are 8.4 IPv4 addresses per km2. Not counting the oceans, that would be 28 IPv4 addresses per km2 of land. IPv6 gives 10^17 addresses per mm2 (yes, square millimeter). In terms of volume, 10^8 IPv6 addresses per mm3 throughout the Earth.
  - diggan 3y ago
    Since you seem to know what you're talking about: Imagine a scenario where we have nano-bots to perform "repairs" in our bodies or whatever, and obviously each individual nano-bot use TCP over IPv6 because future software developers are also as lazy as us. Instead of taking paracetamol, people take nano-bot-shots which include (presumably) millions (or even billions?) of nano-bots that we inject into our bodies. However, they disappear after a week (or some other more realistic timeline). Now, how many people can use these on a monthly basis before we run out of IPv6 addresses?
    - ninkendo 3y ago
      https://xkcd.com/865/ https://xkcd.com/865/
    - Rudism 3y ago
      Are you implying that we would assign a public /64 subnet to a collection of nanites that were designed to be absorbed after a week in the human body, and then retire that subnet forever? This seems like an unlikely scenario, but I'll assume it's just an intellectual exercise and take a stab! - Total number of /64 subnets available: 2^64 - Total number of humans in this future: Let's say 16 billion (roughly twice what we're at now) To get the total number of months before we'd run out of /64 subnets, assuming each human is absorbing one every month, we divide the number of /64 subnets by the number of humans: 2^64 / 16 billion =~ 1,152,921,505 Divide by 12 to get the total number of years: 1,152,921,505 / 12 =~ 96,076,792 So by my math, assuming the human population stayed steady at 16 billion (which seems just as absurd as the initial premise) we'd have about 100 million years to figure out how to start reusing some of those old subnets before we started running into trouble.
- soneil 3y ago
  The space currently assigned to globally routable addresses is 1/8th of the v6 address space. Over 50% of the addressable space is currently reserved. The numbers are frankly mind-bending. Even if we we make a complete pigs ear of assigning billions of IPs to billions of networks in the current /3, we have space for more than one do-over. But I do believe there's a higher chance the next /3 will be assigned to Mars.
sam1r 3y ago
[flagged]
dheera 3y ago
I grew up with IPv4 (1.2.3.4) and I was expecting IPv6 to just be 1.2.3.4.5.6 with backward compatibility so that 1.2.3.4 would just be 0.0.1.2.3.4 and the 1.2.3.4 dude wouldn't need to change their address. And the IPv8 would be 0.0.0.0.1.2.3.4 whenever we need it, but probably not for a long time When I saw all the double-colons and slashes and monstrosities like f00f:00f:::ea//dead::beef/3 I just kept using IPv4. I can't even remember Google's IPv6 DNS ffs. 8.8.8.8 was easy to remember. Now it's got some hex bullshit in it and a double colon thrown in somewhere.
- Plasmoid 3y ago
  Another person who does not understand IPv4. IPv4 isn't a text based protocol where IP addresses are parsed like DNS. It's a binary protocol where addresses are recorded in binary and adding more address space WOULD BE A BREAKING CHANGE.
  - schroeding 3y ago
    For a practical demonstration: That's the reason decimal IPs work, too - i.e. http://3520653007/ http://3520653007/ is the same as http://209.216.230.207/ http://209.216.230.207/ (and both will go to HN) - it's all just nice formating for our human brains. Nothing would stop us from formatting IPv6 the IPv4 way except the monstrous length of the resulting address.
    - TrickyRick 3y ago
      Wow learned something new today. What's interesting is that the decimal representation looks more like a phone number which people would be used to. Interesting that IP addresses as they are written today was the format that won, as a kid before learning how computers worked I always found it weird how 255 was the highest number in each group.
      - vel0city 3y ago
        Its often challenging enough for people to do CIDR subnet calculations in their head when its broken out into octets. I'd have just given up on networking entirely if the standard was to use decimal notation.
globular-toast 3y ago
I grew up with IPv4 too but after learning and configuring my network for IPv6 I won't miss v4 at all. It's just so nice having each device with its real IP address rather than some private NAT thing. Then it's just firewall config if you want to run servers etc rather than messing with NAT configs.
- ninkendo 3y ago
  Agreed. My favorite part is that you don’t need any special consideration for local/WAN splits in DNS. Your DNS address for your homelab server is the same address on your LAN as it is on the WAN, so your DNS can just be the same. Thus “ssh hostname.fqdn” works whether you’re on the local network or remote, and your packets just automatically stay on your LAN when you’re local (they don’t even have to hit your router… they can directly unicast if you’re on the same switch. No “hairpin NAT” or anything like that needed.)
- gary_0 3y ago
  Doesn't that mean if you move, or if your ISP changes your IP, all your local devices will end up with different addresses? I have an internal DNS server and it would be annoying if it could randomly break and require me to update all the IPs.
  - op00to 3y ago
    My local devices end up with new ipv6 addresses daily.
    - gary_0 3y ago
      So if I'm checking local server log files to debug a problem that started a few days ago, I can't easily tell where the incoming connections are coming from?
      - op00to 3y ago
        You can configure a static ip if you use IP addresses as an identifier. You can also keep track of who had what ip address.

p-e-w 3y ago

The last time I looked into this (which was a few years ago), ISPs were allocating blocks containing billions of IPv6 addresses to anyone who paid a nominal sum. So that vast address space might not last as long as it would seem...

internetter 3y ago
We never learn
greyface- 3y ago
That sure sounds like a lot. But "billions" is less than a /64. Try "sextillions" (/56) or "septillions" (/48). Of course, when the denominator is "undecillions", it becomes clear that this is actually a non-issue.
- joering2 3y ago
  I'd even go out of my way and say that undecillion of IP addresses ought to be enough for anybody.
  - dns_snek 3y ago
    Bold prediction! Let's see if it holds true in 200 years when every cybernetic cell in your body is individually addressable from the public internet.
    - ale42 3y ago
      This is almost IPv9 (RFC1606)! https://datatracker.ietf.org/doc/html/rfc1606 https://datatracker.ietf.org/doc/html/rfc1606 The up to 42 deep hierarchy of routing levels built into IPv9 must have been one of the key features for its wide deployment. [...] As yet, no requirement has been found for levels 40-42, with level 39 still being used for experimental interrogation of atomic structure of components where required. Of course, it's a 1st April RFC. For those who don't know them, see https://en.wikipedia.org/wiki/April_Fools'_Day_Request_for_Comments https://en.wikipedia.org/wiki/April_Fools'_Day_Request_for_C...: they include thinks like terminals with subliminal messages, IP over pigeons...
    - Nition 3y ago
      98% of all IPv6 addresses will be set aside for self-replicating nanobots and our bodily cells will have to fight over only the remaining 2%.
- mike_d 3y ago
  ARIN recently handed out a /16 allocation to Capital One. That is one 65,025th of all of IPv6. A reasonable sized /32 allocation would have allowed for giving every ATM they operate worldwide its own globally routable /48.
  - greyface- 3y ago
    Too bad ARIN tickets aren't public - I would love to read the one in which that was justified. Reading NRPM 6.5.2.1, it seems that they must have submitted documentation claiming at least 2^28 distinct serving sites in order to qualify for an assignment that large.
  - ta1243 3y ago
    I find the insistence of using /64s everywhere for networks frustrating. Any network larger than a /112 seems crazy, that's already 65k IPs per subnet. A /104 for every normal end user (256 subnets per user), or a /80 for massive companies like Capital One (4 billion subnets) should be more than enough.
    - tuetuopay 3y ago
      There is a really practical reason behind this, and it is called "routers". Due to longest prefix match, you'll end up wasting resources on the networking hardware. And you waste both precious and expensive TCAM and LPM latency for matching the prefixes. So routers do optimize for anything shorter than /64, and have special lookup memory for /64 and /128. But nothing in-between.
      - ta1243 3y ago
        That's fair enough, in which case ipv6 is really only a /76 (having more than 1000 hosts on a subnet isn't a great thing, even with no broadcast and arp and other traffic, and /76 allows 4000 on a /64) Those fanboys going "we'll never run out of 2^128 IPs" are being disingenuous when about 2^59 of them have been burnt straight away (I'd guess most subnets have less than 30 devices) 2^64 subnets is a reasonable number, but when they are handed out like candy that number dwindles quickly. ARIN is allocating the equivalent of a /15 every year. That's fine if it's a constant allocation, there's 100,000 years worth, but if that rate grows, the space will be eaten in a matter of a few decades.
- iLoveOncall 3y ago
  I'm sure people said exactly this about IPv4 back in the days.
  - dns_snek 3y ago
    Can you even begin to imagine a use case that could come close to exhausting an IP space that is perfectly capable of assigning a /60 subnet to every single grain of sand on earth? That subnet is large enough to then assign an IP address to every individual atom in that grain of sand. For comparison, if we wanted to assign every living person on Earth a grain of sand, we would only need a few cubic feet of it (less than 1 cubic meter).
    - corobo 3y ago
      Nanites might give you a good start Of course we'd all be paperclips long before they need to worry about networking
    - diggan 3y ago
      > Can you even begin to imagine a use case that could come close to exhausting an IP space that is perfectly capable of assigning a /60 subnet to every single grain of sand on earth? As parent said, I'm sure people made the exact same argument about IPv4 back in the day, but comparing it to something else. And when IPv16 finally appears in the future, people will yet again make exactly the same argument.
      - dns_snek 3y ago
        > As parent said, I'm sure people made the exact same argument about IPv4 back in the day, but comparing it to something else. You're ignoring the sheer scale of this question. We don't have enough raw materials on this planet, or likely in the observable universe, to produce enough devices that would consume that many IPs. We could colonize 1 billion planets. Each of those planets could have 100 billion people. Each of those 100 billion people could own 1 billion "things" that could be considered "networked devices". Each of those "things" could consume 1 billion IPs. We could have all that, and we would still have 70% of the IPv6 space left. > The decision to put a 32-bit address space on there was the result of a year’s battle among a bunch of engineers who couldn’t make up their minds about 32, 128 or variable length. And after a year of fighting I said — I’m now at ARPA, I’m running the program, I’m paying for this stuff and using American tax dollars — and I wanted some progress because we didn’t know if this is going to work. So I said 32 bits, it is enough for an experiment, it is 4.3 billion terminations — even the defense department doesn’t need 4.3 billion of anything and it couldn’t afford to buy 4.3 billion edge devices to do a test anyway. So at the time I thought we were doing a experiment to prove the technology and that if it worked we’d have an opportunity to do a production version of it. Well — [laughter] — it just escaped! — it got out and people started to use it and then it became a commercial thing. - https://www.youtube.com/watch?v=mZo69JQoLb8&t=816s https://www.youtube.com/watch?v=mZo69JQoLb8&t=816s They were contemplating 128 bits addresses all the way back then, but settled on 32 bits as a mere proof of concept that got out of hand.
pilif 3y ago
One of the features of IPv6 is address autoconfiguration, obviating the need for a central authority like DHCP on v4. However, that only works with a /64 prefix and given that larger sites might want to have multiple subnets, that’s why most assignments are /56 or /48. But still. If all assignments were /48s, that would still leave room for 281 trillion networks which even I believe is enough for the foreseeable future. If the number space is so big, it makes sense to take advantage of it if that allows for other additional features (like SLAAC)
- londons_explore 3y ago
  > However, that only works with a /64 prefix Well it should be redesigned so it works all the way down to individual addresses.
  - greyface- 3y ago
    You can use DHCPv6 instead of SLAAC if you need autoconfiguration on sub-/64 prefixes.
    - scheme271 3y ago
      Some systems like android don't support anything but SLAAC
      - ale42 3y ago
        IMHO it means that they are not fully IPv6 compliant. Corporate networks often have DHCPv6 rather than just SLAAC.
        bert64 3y ago
        They are fully compliant, SLAAC is part of the standard whereas DHCPv6 is an optional extra. DHCPv6 also does not work without RA. DHCPv6 just assigns an address, a routable prefix, dns servers etc, it does not assign a subnet or any routes, you need route advertisements for that.
Kab1r 3y ago
Billions of addresses might seem like a lot, but every IPv6 network has at least 2^64 addresses and it doesn't make much sense (to me) to give any customer less than one network. (Maybe you meant billions of /64 blocks? ISPs could be providing a /32 ≈ 4 billion /64 blocks, though there still are 2 billion of those in the entire IPv6 space)
porbelm 3y ago
ISPs are SUPPOSED to allocate a /64 for a single customer. Mine does, so I have 4.5 billion available addresses within my 2001:4653:nnnn:nnnn::/64 prefix...
- ptman 3y ago
  2^32 is ~4.3*10^9 2^64 = 2^32 * 2^32 , so quite a bit more
- cesarb 3y ago
  > ISPs are SUPPOSED to allocate a /64 for a single customer. Weren't they supposed to allocate a /48? Or did that change while I wasn't looking?
  - greyface- 3y ago
    > Or did that change while I wasn't looking? Yes: https://datatracker.ietf.org/doc/html/rfc6177 https://datatracker.ietf.org/doc/html/rfc6177
throw0101d 3y ago
> So that vast address space might not last as long as it would seem... Have you done the math? * math property: x^y = x^(a+b) = (x^a )x(x^b ) * IPv4 addresses are 32 bits (2^32 ) * 2^32 ~ 4.3 billion * So the IPv4 Internet has ~4.3B devices on it * IPv6 subnets are 64 bits, /64 (2^64 ) So, a IPv6 2^64 subnet is the same as (2^32 )x(2^32 ), which means (4.3B)x(IPv4 Internet). I.e., a single IPv6 subnet can hold the equivalent of four billion (IPv4) Internets. A second way of thinking about it: * Stars in the Milky Way: 400 Billion * Galaxies in the universe: 2 Trillion So (4x10^11 )x(2x10^12 )=8x10^23 stars in the universe. * Size of IPv6 address space: 3.4x10^38 Find the ratio between addresses and stars: * 3.4x10^38 / 8x10^23 IPv6 offers about 430 trillion times more addresses than estimated stars in the universe. A third way: On the surface of the Earth (land+water), there are 8.4 IPv4 addresses per km2. Not counting the oceans, that would be 28 IPv4 addresses per km2 of land. IPv6 gives 10^17 addresses per mm2 (yes, square millimeter). In terms of volume, 10^8 IPv6 addresses per mm3 throughout the Earth.
- diggan 3y ago
  Since you seem to know what you're talking about: Imagine a scenario where we have nano-bots to perform "repairs" in our bodies or whatever, and obviously each individual nano-bot use TCP over IPv6 because future software developers are also as lazy as us. Instead of taking paracetamol, people take nano-bot-shots which include (presumably) millions (or even billions?) of nano-bots that we inject into our bodies. However, they disappear after a week (or some other more realistic timeline). Now, how many people can use these on a monthly basis before we run out of IPv6 addresses?
  - ninkendo 3y ago
    https://xkcd.com/865/ https://xkcd.com/865/
  - Rudism 3y ago
    Are you implying that we would assign a public /64 subnet to a collection of nanites that were designed to be absorbed after a week in the human body, and then retire that subnet forever? This seems like an unlikely scenario, but I'll assume it's just an intellectual exercise and take a stab! - Total number of /64 subnets available: 2^64 - Total number of humans in this future: Let's say 16 billion (roughly twice what we're at now) To get the total number of months before we'd run out of /64 subnets, assuming each human is absorbing one every month, we divide the number of /64 subnets by the number of humans: 2^64 / 16 billion =~ 1,152,921,505 Divide by 12 to get the total number of years: 1,152,921,505 / 12 =~ 96,076,792 So by my math, assuming the human population stayed steady at 16 billion (which seems just as absurd as the initial premise) we'd have about 100 million years to figure out how to start reusing some of those old subnets before we started running into trouble.
soneil 3y ago
The space currently assigned to globally routable addresses is 1/8th of the v6 address space. Over 50% of the addressable space is currently reserved. The numbers are frankly mind-bending. Even if we we make a complete pigs ear of assigning billions of IPs to billions of networks in the current /3, we have space for more than one do-over. But I do believe there's a higher chance the next /3 will be assigned to Mars.

sam1r 3y ago

[flagged]

dheera 3y ago

I grew up with IPv4 (1.2.3.4) and I was expecting IPv6 to just be 1.2.3.4.5.6 with backward compatibility so that 1.2.3.4 would just be 0.0.1.2.3.4 and the 1.2.3.4 dude wouldn't need to change their address. And the IPv8 would be 0.0.0.0.1.2.3.4 whenever we need it, but probably not for a long time When I saw all the double-colons and slashes and monstrosities like f00f:00f:::ea//dead::beef/3 I just kept using IPv4. I can't even remember Google's IPv6 DNS ffs. 8.8.8.8 was easy to remember. Now it's got some hex bullshit in it and a double colon thrown in somewhere.

Plasmoid 3y ago
Another person who does not understand IPv4. IPv4 isn't a text based protocol where IP addresses are parsed like DNS. It's a binary protocol where addresses are recorded in binary and adding more address space WOULD BE A BREAKING CHANGE.
- schroeding 3y ago
  For a practical demonstration: That's the reason decimal IPs work, too - i.e. http://3520653007/ http://3520653007/ is the same as http://209.216.230.207/ http://209.216.230.207/ (and both will go to HN) - it's all just nice formating for our human brains. Nothing would stop us from formatting IPv6 the IPv4 way except the monstrous length of the resulting address.
  - TrickyRick 3y ago
    Wow learned something new today. What's interesting is that the decimal representation looks more like a phone number which people would be used to. Interesting that IP addresses as they are written today was the format that won, as a kid before learning how computers worked I always found it weird how 255 was the highest number in each group.
    - vel0city 3y ago
      Its often challenging enough for people to do CIDR subnet calculations in their head when its broken out into octets. I'd have just given up on networking entirely if the standard was to use decimal notation.

globular-toast 3y ago

I grew up with IPv4 too but after learning and configuring my network for IPv6 I won't miss v4 at all. It's just so nice having each device with its real IP address rather than some private NAT thing. Then it's just firewall config if you want to run servers etc rather than messing with NAT configs.

ninkendo 3y ago
Agreed. My favorite part is that you don’t need any special consideration for local/WAN splits in DNS. Your DNS address for your homelab server is the same address on your LAN as it is on the WAN, so your DNS can just be the same. Thus “ssh hostname.fqdn” works whether you’re on the local network or remote, and your packets just automatically stay on your LAN when you’re local (they don’t even have to hit your router… they can directly unicast if you’re on the same switch. No “hairpin NAT” or anything like that needed.)
gary_0 3y ago
Doesn't that mean if you move, or if your ISP changes your IP, all your local devices will end up with different addresses? I have an internal DNS server and it would be annoying if it could randomly break and require me to update all the IPs.
- op00to 3y ago
  My local devices end up with new ipv6 addresses daily.
  - gary_0 3y ago
    So if I'm checking local server log files to debug a problem that started a few days ago, I can't easily tell where the incoming connections are coming from?
    - op00to 3y ago
      You can configure a static ip if you use IP addresses as an identifier. You can also keep track of who had what ip address.