"Kevin" == Kevin Oberman <oberman@es.net> writes:
Kevin> This is really pretty silly. Not really, Joe may actually have a point here. Kevin> Only end nodes will auto-configure with the MAC address Kevin> used for 48 bits of the IPv6 address. Exactly how this is a Kevin> serious privacy issue continues to elude me, but I suppose Kevin> that the paranoid may want to change it to some things Kevin> else. (And change it on an hourly basis, if they are REALLY Kevin> paranoid.) The reason for EUI64 is to provide a sensible default for the end system address. Yes it is possible for anyone with sufficient motivation to use something else, but the vast majority of users will just plug their in laptops and get an address. What information can be reconstructed from this? For a mobile user, you could construct a list of the providers and POPs that they tend to use. This means that when I use google, they can easily tell that I live in abc neighborhood and work at xyz company and tend to spend time surfing the web at my friend's place across town. That is, you can infer patterns of physical movement of the device and the user. The worry is not so much about the people with the technical savvy to randomize their addresses, but about everybody else that is not even aware that they're making themselves and their movements conveniently identifiable. Don't credit cards and cell phones do the same thing? Yes, it is the same problem. But in those cases, at least there are more barriers to getting at and using the information... In theory... Kevin> God help us all if some discovers that I use both Intel and Kevin> 3Com cards! (Not to mention Agere on occasion.) Just wait until you start getting targeted advertising from Realtek! ;) -w