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0 pointstsimionescu2y ago0 comments

Your initial claim was that a IPv6 address consists of a 64-bit network address, then a 64-bit device address that could be separated into <site-id>:<vlan> as an example.

However, SLAAC demands that each device is given a 64-bit prefix that it then chooses many random 64-bit host addresses from, without any other rhyme or reason. So, if you want to know the IP of a host you want to connect to, you have to remember at least a 64-bit number that changes every day by design. Add to that some extra bits for the particular part of the network you are in.

So your IPv6 is more like <isp-assigned-prefix, 32-56 bits>:<internal-net-prefix, 8-32 bits>:<random-host-address, 64 bits>. Human friendly this is not.

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nerdbert2y ago

> you have to remember at least a 64-bit number that changes every day by design

A machine using IPv6 privacy extensions would have two addresses; one that changes, and one typically based on the MAC address that remains constant.

If you are in the local network with that machine or otherwise are supposed to be in-the-know, you'd know it's fixed address and connect to that.

tsimionescuOP2y ago

That's OK if you're directly trying to access the machine, but it's not enough if you're looking through logs to try to understand which of your machines is contacting you.

welterde2y ago

No it was not. My claim was that the network address part (the first 64-bit) can be separated into <network>:<site-id>:<vlan>.. etc.

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