On Sat, Jun 4, 2011 at 9:46 PM, Stephan Somogyi <[email protected]> wrote: > "So what is AES? It's a unique pre-programmed 128-bit encryption key which > is designed to help prevent your keystrokes, which are transmitted > over-the-air, from being intercepted and deciphered." > > I just discovered the preceding at: > <http://microsofthardwareblog.com/wireless-desktop-2000/>. > > Neither the Product Guide nor the Technical Data Sheet provide details. > > Is there really only a single hardwired key for the kbd/receiver pair as the > text suggests?
Are you asking if there is only a single hardwired key for that is the same for *all* keyboard / receiver pairs? That would be insane. I certainly did NOT get that impression. I thought they just meant that each keyboard/mouse and receiver had a fixed, but unique AES key hardwired into it. Or perhaps you are simply saying that they are susceptible to timing attacks just because they use a single fixed key? While that _could_ be true for their given implementation, I don't think that that necessarily follows just because a single keyboard/receiver, mouse/receiver pair uses a single fixed key. If they use random IVs and appropriate cipher mode or couple the ciphertext with an HMAC to ensure message authenticity, I think they should be OK. However, without technical details, it's impossible to tell. And if they did something stupid like basing the AES key on a serial #, that would not bode well either. (Even if they used an HMAC of the S/N "signed" by a secret held only by Microsoft, that's way too brittle...someone steals that one secret and it would be game over.) OTOH, I suppose one could argue that this better than your normal wireless keyboard which is just communicating over an unencrypted channel. (Yes, there's always the danger if Microsoft totally botched it and no one knows that one might get the illusion of security. However if one is close to pick up wireless signals, than Van Eck phreaking is also probably a possibility. So probably not suitable for spys. ;-) Just my $.02. Maybe one of the real cryptographers on this list will give you a more authoritative answer. -kevin -- Blog: http://off-the-wall-security.blogspot.com/ "The most likely way for the world to be destroyed, most experts agree, is by accident. That's where we come in; we're computer professionals. We *cause* accidents." -- Nathaniel Borenstein _______________________________________________ cryptography mailing list [email protected] http://lists.randombit.net/mailman/listinfo/cryptography
