Re: Activation protocol for tracking devices

2009-03-04 Thread Santiago Aguiar
David Wagner wrote: This does sound like it introduces novel risks. I would suggest that rather than spending too much energy on the cryptomath, it would make sense to focus energy on the systems issues and the security requirements. Very interesting read. These topics are being discussed,

Activation protocol for tracking devices

2009-03-02 Thread Santiago Aguiar
I'm afraid this email will probably will be a) flamed away (because it's not from a cryptographer, but forced to do crypto-things, and I do know your opinion about this matter...) b) ignored (same reason!). I'm sending it anyway because any kind of feedback would be welcomed ;), and the

Re: Activation protocol for tracking devices

2009-03-02 Thread Santiago Aguiar
Hi, Jerry Leichter wrote: Not specifically, but you can simply take the first 64 bits from a larger cryptographically secure hash function. OK, I didn't know if it was right to do just that. We were thinking to use that hash in an HMAC so the TCU and SO can know that they were originated from

Re: Activation protocol for tracking devices

2009-03-02 Thread Santiago Aguiar
John Ioannidis wrote: Just don't do it. If you are going to spend your energy on anything, it should be to work against such a plan. I would agree, but I fear that a this is never going to work, drop it will be less heard than any effort in at least trying to raise the bar for an attack.

Brazilian mandatory vehicle anti-theft and tracking regulation

2009-02-23 Thread Santiago Aguiar
Hello, I have been following this list for some time, and I wanted to comment on one of the projects I'm working on, just to hear your comments about it (and because I think is quite interesting for its security implications...). Starting on August 2009, all new Brazilian vehicles will need