Re: gbde blackening feature - how can on disk keys be destroyed thoroughly?

2004-09-05 Thread Poul-Henning Kamp
In message [EMAIL PROTECTED], David Kreil writes: On a modern disk there is no sequence of writes that will guarantee you that your data is iretriveable lost. Even if you rewrite a thousand times, you cannot guard yourself against the sector being replaced by a bad block spare after the first

Re: gbde blackening feature - how can on disk keys be destroyed thoroughly?

2004-09-05 Thread David Kreil
Dear Poul-Henning, On a modern disk there is no sequence of writes that will guarantee you that your data is iretriveable lost. Even if you rewrite a thousand times, you cannot guard yourself against the sector being replaced by a bad block spare after the first write. Good point. In

Re: gbde blackening feature - how can on disk keys be destroyed thoroughly?

2004-09-04 Thread Poul-Henning Kamp
In message [EMAIL PROTECTED], David Kreil writes: Hi, From what I can see so far, they are simply overwritten with zeros - is that right? If so, the blackening feature would be much weakend, as once can read up to 20 layers of data even under random data (and more under zeros). I would be

Re: gbde blackening feature - how can on disk keys be destroyed thoroughly?

2004-09-04 Thread David Kreil
Dear Poul-Henning, Thank you very much for your comments! From what I can see so far, they are simply overwritten with zeros - is that right? If so, the blackening feature would be much weakend, as one can read up to 20 layers of data even under random data (and more under zeros). I

Re: gbde blackening feature - how can on disk keys be destroyed thoroughly?

2004-09-03 Thread David Kreil
Hi, From what I can see so far, they are simply overwritten with zeros - is that right? If so, the blackening feature would be much weakend, as once can read up to 20 layers of data even under random data (and more under zeros). I would be most grateful for comments, or suggestions of

Re: gbde blackening feature - how can on disk keys be destroyed thoroughly?

2004-09-03 Thread Len Zettel
On Friday 03 September 2004 07:18 pm, David Kreil wrote: Dear Vijay, I guess I took this off the list. It's OT, in my oppinion. Oh. Anywhere more appropriate to send it to that you could suggest at all? Now also trying freebsd-geom - would that have been the better place to send this to to

Re: gbde blackening feature - how can on disk keys be destroyed thoroughly?

2004-09-03 Thread Vijay Kaul
On Fri, 03 Sep 2004 19:41:18 -0400, Len Zettel [EMAIL PROTECTED] wrote: snip While i am not an expert in this area, I can not help but wonder--- Who are you worried about recovering the data, under what circumstances? My best guess is that recovering anything from even _one_ data over-write is

Re: gbde blackening feature - how can on-disk keys be destroyed thoroughly?

2004-09-03 Thread David Kreil
Dear LenZ, Who are you worried about recovering the data, under what circumstances? The value of the blackening feature should be that you can give away the drive and your password, say, under pressure by the [court|mafia|whoever], without compromising any confidential information on the