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Comment by wolvoleo | Hacker News Reader

Yeah but that ridiculous overdimensioning is something I object to. There's more IPs than is needed to give each grain of sand on this planet its whole IPv4-sized internet. That's just overkill.

And the problem seems to be solving itself as the world is turning its back on globalism. China and North Korea already have separated themselves. Iran too. China still uses the same address space but it's not like there's open connectivity with the rest of the world. We'll probably cut off Russia at some point completely as part of some sanction (they've been preparing for that for years), and Europe will break with America if things continue. We'll just have interoperability at a few controlled border points then, like China already does with its great firewall. It'll be easy to do some address translation then.

Ps that's not something I'm necessarily happy about but I do see this trend emerging of every region trying to wall itself off.

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> Yeah but that ridiculous overdimensioning is something I object to. There's more IPs than is needed to give each grain of sand on this planet its whole IPv4-sized internet. That's just overkill.

People also thought that 4 byte wide IPv4 Adresses would be large enough. It's really hard to estimate how much you will need. And because numbers are effectively a free resource, it is better to overestimate.

IPv6 also gives you shortcuts to write addresses. You can abbreviate the longest run of zeroes with `::` and leading zeroes within a hextet can be omitted. This makes IPv6 address notation elastic.

Well considering the 4 bytes were designed in the time of a small research network between defense and universities, it's great foresight that they made it as big as it is. It still runs most of the internet to this day.

But it's not free, after all every packet carries this burden. I know about the annotation but it also makes it very difficult to parse.

That's basically no burden at all. If we cut the address length down to increase throughput, we would get a one-time increase of about 0.8% -- but consider how much faster Internet connections have gotten over the past 30 years. They've improved by about 0.8% per week on average. You're worrying about something that's smaller than one or two weeks of natural progress in Internet connection speeds

Rather than trying to minmax the address length, it makes more sense to sacrifice a few bits per packet to the addresses, wait a week or two on average to get the lost throughput back, and then spend those bits elsewhere to make other things easier. (For example, avoiding NAT is an obvious one, but even just "everything is a /64" removes the need to ever need to think about the size of a network.)

If you can spend a few address bits to make something easier elsewhere, that's a good trade. Maybe start worrying if the addresses were a kilobit long or something, but they aren't even close to that.

What ridiculous overdimensioning? L2 addresses are 64 bits, and L3 has to be bigger than L2 because L3 acts as an aggregation layer over L3. From staring at RFC 3194, I'd say the minimum size for L3 is about 80 bits.

v6 is 128 bits, which is the smallest power of 2 that's bigger than 80 and is only an extra 48 bits. Is that really enough to qualify for a claim of "ridiculous overdimensioning"? Especially when we really, really don't want to discover down the line that we made it too small and now need to migrate to another L3 protocol?

I get that the resulting number of IPs is big, but... so? Everything deals with the 128-bit long addresses, not the 2^128-entry long list of IPs. There's no need to care about the latter, just like there's no need to care about the number of potential RSA2048 keys or whatever.

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