Comment by tsimionescu | Hacker News Reader

Comment by tsimionescu | Hacker News Reader

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A basic problem with the IPv6 dotted quad is the fact that it is a quad. Humans can easily discern at a glance at most 3 symbols, which is a major point in favor of the IPv4 decimal notation. It's easier to visually distinguish 101 from 110 than it is to distinguish 1011 from 1101, especially in the context of multiple such groups.

Also, your "your site" example is deceptively simple. It works nicely if your /48 happens to be full of 0s, but even assuming you were allocated a huge /32 and you got to choose the extra 16 bytes for memorability, the address is more likely to be something like 2a00:1450:4001:830::/48.

Even this seems overly optimistic. For example, www.google.com is not a /48, but seems to be closer to /124 from some basic probing: 2a00:1450:4001:830::2000 to 2a00:1450:4001:830::200f seem to all respond as www.google.com, but 2a00:1450:4001:830::2010 does not.

If Google chose not to allocate a whole /48 to www.google.com, I doubt many sites would.

So we're on the page, when I say "site" in this case it means a location to which lots of traffic for many different hosts is routed. (Not "site" as in "website".)

Typically a University campus, or a company office block, or a datacentre, or your whole distributed org if you hang the networks for your other global offices off VPNs behind one front-end site.

Oops, thanks for the clarification, I honestly misunderstood.

I wish more corrections were taken this way. Kudos.

Having been allocated a /32 I think there is some confusion here. You still assign /48s to sites. Sites being physical locations your routers are at, not websites. Inside a site you assign /64 networks per VLAN, such as site:12::/64. Devices in that VLAN can dynamically get an address or be assigned one such as the printer so site::12::4/64 is your printer 4 on the 12th subnet at your 16 bit site prefix of your 32 bit global scope. Smaller orgs may have less than 16 bits for their site prefixes, all the way down to just having a single /48 assigned to them.

This is similar to how many smaller orgs used 10.site.vlan.device but obviously it scales larger (site and vlan can each be 16 bits instead of 8) and everybody gets a unique public replacement for "10."

>Humans can easily discern at a glance at most 3 symbols

Are you sure about this, or have a source where I can read more? There are some counterpoints: both Japanese and Chinese use four-digit grouping for numbers, and it's common to see things like credit cards use four-digit groups.

Not OP and not my field of study but this seems relevant.

>Variations in the amplitude of the N400 showed a better memory trace for items presented in [temporal groups] of three compared to those in groups of four.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3959615/

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