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by apearson 1198 days ago
fd::1 == 00fd::1. The :: expands to fill the available bits with 0
1 comments
p1mrx 1198 days ago
fd::1 == 00fd::0001, which is reserved by IETF.

The :: only expands to fill all-zero hextets.

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apearson 1198 days ago
Good catch, that is correct. Thank you
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hot_gril 1198 days ago
...This thread shows that the ipv6 notation is more complicated. It's good to at least use a smaller address space on a LAN like this, but I want the basic decimal notation.
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p1mrx 1198 days ago
Decimal is actually a nightmare for dealing with common CIDR prefixes. Would you rather write '1111111111110000' as fff0 or 65520?
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hot_gril 1198 days ago
Yes, which is why they shouldn't use those huge prefixes. There's an existing 32-bit address space represented nicely like 8.8.8.8 or 192.168.1.2 for local. Now that we want to extend the address space for more users, the newer ones can be like 8.8.8.8.6 without messing with the existing ones.

Oh and I'd actually prefer the 65520.

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apearson 1198 days ago
You'd still need to upgrade and change every device. There have been transitional software that used ipv6 but allowed for ipv4 address notation. [1] Example: ::ffff:0:8.8.8.8

The huge prefixes allow for a simple hierarchical network structure and gives us room to redo the address scheme if we end up wanting to (only a portion of addresses space is currently allocated right now) without having to go through this entire upgrade the internet again.

[1] https://en.wikipedia.org/wiki/IPv6_transition_mechanism

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