From: pjb@... (Pascal J. Bourguignon)
Date: 2009-01-13T18:49:22+09:00
Subject: Re: Unique identify computer (both Windows and MacOSX)

Brian Candler <b.candler@pobox.com> writes:

> Pascal J. Bourguignon wrote:
>> If Internet connectivity cannot be assumed, then you would have to
>> build a unique ID trying to gather specific data and random data to
>> reduce the probabilities of a collision.  There are several web pages
>> indicating how to build such an ID.
>
> There is a uuid gem too.
>
>> The point is that the specific
>> data about the computer is gathered only when the ID is made, not when
>> it's used.  If you change your hardware configuration, or move your
>> "OS" to some other hardware, you should be able to keep your ID.
>
> But if you store it on the hard drive, then the uid moves with the hard 
> drive. If you backup and restore to another machine, then you will have 
> two machines with the same uid.

Yes, exactly.  Why would you want to forbid the user to do that. After
all, it's him who pays for that software, no?

-- 
__Pascal Bourguignon__