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A comment on I spent a week without IPv4 to understand IPv6 transition mechanisms. Parent comment

Re:I spent a week without IPv4 to understand IPv6 transition... by ianburrell on Monday March 06, 2023 @12:23PM (#35043860)
Why would changing N seconds break network? It would presumably keep active addresses until connections finish. IPv6 requires supporting multiple addresses per interface.

More reasonable is to use new address for each connection. Then nobody can tell if 10 addresses and 10 connections are one device or ten.

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Re:I spent a week without IPv4 to understand IPv6 transition... by waych on Monday March 06, 2023 @12:38PM (#35044301)
This looks like NAT pushed down to the endpoint itself.

You've saved the translation in the router, but now routing lookups and ARP caches have grown by TEMP_VALID_LIFETIME / TEMP_PREFERRED_LIFETIME.

What are valid values in the scenario you are proposing? The defaults are 1 week / 1 day, so 7X. If you chose to rotate each second, and say allowed addresses to only be valid for say 20 minutes, this still appears to be a ~1200X blowup in routing overheads.

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Re:I spent a week without IPv4 to understand IPv6 transition... by kazen44 on Monday March 06, 2023 @03:56PM (#35047469)
> You've saved the translation in the router, but now routing lookups and ARP caches have grown by TEMP_VALID_LIFETIME / TEMP_PREFERRED_LIFETIME.

They have not?

The global routing table size for ipv6 at max is a /32 (if i remember correctly) every customer gets a /56 prefix to use in their network, so the routing table entry would still be the same, no matter how many addresses you use to cycle through in your /64.

ARP caches do not exist in IPv6, and Neighbour discovery does not have the same "cache" mechanism as ARP does, it uses an entirely different mechanism for neighbour discovery. (which is also far more lightweight considering it is using multicast, compared to the broadcast of ARP).

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Re:I spent a week without IPv4 to understand IPv6 transition... by waych on Monday March 06, 2023 @09:49PM (#35050937)
I don't understand what you mean. Neighbor Discovery Caches certainly are a thing.
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