Subj : SLAAC Privacy extensions
To   : Kees van Eeten
From : Michiel van der Vlist
Date : Tue Nov 25 2014 13:44:11

Hello Kees,

On Tuesday November 25 2014 12:28, you wrote to Bj”rn Felten:

 KE>  What surprized me is that with some of the incomeing sessions, the
 KE> local part of the address changes. Is that part of the trick to
 KE> confuse identity? For Wilfred I found 9 more or less random values.

Privacy Extensions for Stateless Address Autoconfiguration

https://tools.ietf.org/html/rfc4941

In Windows it is enabled by default. Instead of deriving the host part from the MAC address, it is replaced by a 64 bit random number that is refreshed periodically. By using that instead of the MAC derived SLAAC address for outgoing sessions, it is harder to follow someone when he is moving around with his laptop, table or smartphone.

For a host connected via a fixed line, it does not make much sense. The prefix will lead to your house/office anyway...

You do not see that in my connections because I use the SixXs tunnel endpoint directly for outgoing IPv6 on this machine.


Cheers, Michiel

--- GoldED+/W32-MSVC 1.1.5-b20130111
 * Origin: 2001:470:1f15:1117::1 (2:280/5555)

.