> I thought it used EUI-64 assignments which leaks MAC addresses which is supposed to be a problem for some reason.
You're about a decade (2007) behind the times:
Nodes use IPv6 stateless address autoconfiguration to generate
addresses using a combination of locally available information and
information advertised by routers. Addresses are formed by combining
network prefixes with an interface identifier. On an interface that
contains an embedded IEEE Identifier, the interface identifier is
typically derived from it. On other interface types, the interface
identifier is generated through other means, for example, via random
number generation. This document describes an extension to IPv6
stateless address autoconfiguration for interfaces whose interface
identifier is derived from an IEEE identifier. Use of the extension
causes nodes to generate global scope addresses from interface
identifiers that change over time, even in cases where the interface
contains an embedded IEEE identifier. Changing the interface
identifier (and the global scope addresses generated from it) over
time makes it more difficult for eavesdroppers and other information
collectors to identify when different addresses used in different
transactions actually correspond to the same node.
This document describes an extension to IPv6 Stateless Address
Autoconfiguration that causes hosts to generate temporary addresses
with randomized interface identifiers for each prefix advertised with
autoconfiguration enabled. Changing addresses over time limits the
window of time during which eavesdroppers and other information
collectors may trivially perform address-based network-activity
correlation when the same address is employed for multiple
transactions by the same host. Additionally, it reduces the window
of exposure of a host as being accessible via an address that becomes
revealed as a result of active communication. This document
obsoletes RFC 4941.
You're about a decade (2007) behind the times:
* https://datatracker.ietf.org/doc/html/rfc4941 * https://datatracker.ietf.org/doc/html/rfc8981* https://en.wikipedia.org/wiki/IPv6_address#Stateless_address...