4 ms·

this keeps coming up, if you add a byte to ipv4 you still have a transition problem. 5 byte machines can't talk to 4 byte machines. pretty much the only thing t

this keeps coming up, if you add a byte to ipv4 you still have a transition problem. 5 byte machines can't talk to 4 byte machines. pretty much the only thing that solves is people not liking the :: syntax. the only other change is auto configuration, which...kind of doesn't matter? is that really causing problems?

mahboi 4mo ago
Yeah but they could've picked something that at least lets the 4 byte host talk to a 5 byte one. Like if I have 8.8.8.8 and they want to give me 8.8.8.8.0, cool. Or make it 8 bytes instead of 5, same thing.
- convolvatron 4mo ago
  well, if you want to add an extra byte you kinda have a problem, since v4 is fixed format and is actually cooked into hardware in a lot of places. so if you want to keep v4 mostly untouched you have to use an option, which is going to be pretty slow on the backbone. you can send a packet from an extended address host to a vanilla v4 host if you map the address space into a range like you suggest..but that v4 host just has no way of sending a message back..so its kinda useless
  - mahboi 4mo ago
    It'd be useless until everyone switches to the 5-byte thing and people can start putting something besides 0 into that last byte. But at least they could turn on v5 or whatever it's called without having to think about it. Right now I could have two hosts that both agree to use ipv6 and it's still hard because you have to reconfigure everything.
    - Dagger2 4mo ago
      Why the double standard? v6 already gives you what you're asking for here: you can turn it on without thinking about it, but actually using the extra addresses from it requires reconfiguring some things (not everything, mind). Why is that bad when it's v6 doing it, but good when it's your 5-byte thing doing it? Or did you just not think through this enough to realize you were asking for something we already have?
      - mahboi 4mo ago
        Because you can't generally turn on v6 without thinking about it. Maybe consumers can, even then not always cause it messes random things up. Power users and offices maybe can't. Service operators really can't. If it were as easy as you're saying, all those things like Github would already at least support v6.
        Dagger2 4mo ago
        Windows, Linux, OSX, Android and iOS all ship with v6 enabled by default out of the box, so it's already turned on without you needing to think about it. You have to deliberately go out of your way for this not to be the case. > If it were as easy as you're saying, all those things like Github would already at least support v6. This isn't the "turn it on" stage, it's the "people can start putting something besides 0 into that last byte" stage.
        mahboi 4mo ago
        You need ipv4 to reach GitHub right now. The ipv5 "people can turn it on but not use the last bytes" stage wouldn't require ipv4 to reach it.
        Dagger2 4mo ago
        Do I? I don't have v4 on this machine and I can reach GitHub, so that appears to be untrue. Also GitHub would need to continue having v4 so that v4 users could reach it, so it's untrue from that perspective too. At some point or another, you have to do the work to support longer addresses. In your proposal, where is that work being done? Because right now it looks like you're either massively underestimating how much work it is or you're just outright ignoring it, but only for your own proposal and not for v6.
        mahboi 4mo ago
        Github.com doesn't have an AAAA record, so I don't know how you're reaching it if you don't have a v4 anywhere. Even if they had that, they said that basic features like cloning repos won't work over v6. Only one example of many services like this. > In your proposal, where is that work being done? Work for longer v5 addrs would be similar in difficulty to what v6 had to do, but it'd be done at a different time and place. Only thing that's the same is you need a new packet format that hardware can read, which could literally be the v6 format repurposed. I'd say 8 bytes is enough, leave the rest as 0s. Ipv5 would share routing tables, DHCP, DNS, NAT, and various middleboxes with ipv4, unlike v6 which made separate versions of those with their own state. V5 with 4-byte addrs works with those instantly, no chicken and egg. Then those get patched or replaced to support longer addresses. Importantly, the upgraded versions easily support ipv4 too, so there's no reason not to upgrade.
sherburt3 4mo ago
I think the addresses are a big issue. The address space is just stupid big, I don't understand why we need to prepare for every grain of sand on Earth having a WiFi chip in it. Most people can pick up calculating subnets in their head in ipv4 pretty quickly and ipv4 addresses are easy to memorize on accident. My brain turns to mush as soon as I start seeing hexadecimal characters in addresses.
- Dagger2 4mo ago
  But subnetting in v6 is so much easier than in v4? And it's specifically because of the hex. You don't even need to calculate it, in your head or otherwise, because you just subnet based on characters: 2001:db8:42:1xxx::/52 2001:db8:42:2xxx::/52 2001:db8:42:20xx::/56 2001:db8:42:21xx::/56 2001:db8:42:210x::/60 2001:db8:42:2100::/64 2001:db8:42:2101::/64 etc. About the only mildly complicated thing is remembering that leading zeros in a number can be dropped but trailing ones can't (i.e. 1 and 001 are the same number, but 1 and 100 are different numbers), but that's something you should've learnt in grade school already.
- mahboi 4mo ago
  Because devices randomly generate the last 64 bits of the address without coordinating. They need it to be long to avoid collisions.

mahboi 4mo ago

Yeah but they could've picked something that at least lets the 4 byte host talk to a 5 byte one. Like if I have 8.8.8.8 and they want to give me 8.8.8.8.0, cool. Or make it 8 bytes instead of 5, same thing.

convolvatron 4mo ago
well, if you want to add an extra byte you kinda have a problem, since v4 is fixed format and is actually cooked into hardware in a lot of places. so if you want to keep v4 mostly untouched you have to use an option, which is going to be pretty slow on the backbone. you can send a packet from an extended address host to a vanilla v4 host if you map the address space into a range like you suggest..but that v4 host just has no way of sending a message back..so its kinda useless
- mahboi 4mo ago
  It'd be useless until everyone switches to the 5-byte thing and people can start putting something besides 0 into that last byte. But at least they could turn on v5 or whatever it's called without having to think about it. Right now I could have two hosts that both agree to use ipv6 and it's still hard because you have to reconfigure everything.
  - Dagger2 4mo ago
    Why the double standard? v6 already gives you what you're asking for here: you can turn it on without thinking about it, but actually using the extra addresses from it requires reconfiguring some things (not everything, mind). Why is that bad when it's v6 doing it, but good when it's your 5-byte thing doing it? Or did you just not think through this enough to realize you were asking for something we already have?
    - mahboi 4mo ago
      Because you can't generally turn on v6 without thinking about it. Maybe consumers can, even then not always cause it messes random things up. Power users and offices maybe can't. Service operators really can't. If it were as easy as you're saying, all those things like Github would already at least support v6.
      - Dagger2 4mo ago
        Windows, Linux, OSX, Android and iOS all ship with v6 enabled by default out of the box, so it's already turned on without you needing to think about it. You have to deliberately go out of your way for this not to be the case. > If it were as easy as you're saying, all those things like Github would already at least support v6. This isn't the "turn it on" stage, it's the "people can start putting something besides 0 into that last byte" stage.
        mahboi 4mo ago
        You need ipv4 to reach GitHub right now. The ipv5 "people can turn it on but not use the last bytes" stage wouldn't require ipv4 to reach it.
        Dagger2 4mo ago
        Do I? I don't have v4 on this machine and I can reach GitHub, so that appears to be untrue. Also GitHub would need to continue having v4 so that v4 users could reach it, so it's untrue from that perspective too. At some point or another, you have to do the work to support longer addresses. In your proposal, where is that work being done? Because right now it looks like you're either massively underestimating how much work it is or you're just outright ignoring it, but only for your own proposal and not for v6.
        mahboi 4mo ago
        Github.com doesn't have an AAAA record, so I don't know how you're reaching it if you don't have a v4 anywhere. Even if they had that, they said that basic features like cloning repos won't work over v6. Only one example of many services like this. > In your proposal, where is that work being done? Work for longer v5 addrs would be similar in difficulty to what v6 had to do, but it'd be done at a different time and place. Only thing that's the same is you need a new packet format that hardware can read, which could literally be the v6 format repurposed. I'd say 8 bytes is enough, leave the rest as 0s. Ipv5 would share routing tables, DHCP, DNS, NAT, and various middleboxes with ipv4, unlike v6 which made separate versions of those with their own state. V5 with 4-byte addrs works with those instantly, no chicken and egg. Then those get patched or replaced to support longer addresses. Importantly, the upgraded versions easily support ipv4 too, so there's no reason not to upgrade.

sherburt3 4mo ago

I think the addresses are a big issue. The address space is just stupid big, I don't understand why we need to prepare for every grain of sand on Earth having a WiFi chip in it. Most people can pick up calculating subnets in their head in ipv4 pretty quickly and ipv4 addresses are easy to memorize on accident. My brain turns to mush as soon as I start seeing hexadecimal characters in addresses.

Dagger2 4mo ago
But subnetting in v6 is so much easier than in v4? And it's specifically because of the hex. You don't even need to calculate it, in your head or otherwise, because you just subnet based on characters: 2001:db8:42:1xxx::/52 2001:db8:42:2xxx::/52 2001:db8:42:20xx::/56 2001:db8:42:21xx::/56 2001:db8:42:210x::/60 2001:db8:42:2100::/64 2001:db8:42:2101::/64 etc. About the only mildly complicated thing is remembering that leading zeros in a number can be dropped but trailing ones can't (i.e. 1 and 001 are the same number, but 1 and 100 are different numbers), but that's something you should've learnt in grade school already.
mahboi 4mo ago
Because devices randomly generate the last 64 bits of the address without coordinating. They need it to be long to avoid collisions.