Path: utzoo!attcan!uunet!husc6!mailrus!purdue!decwrl!ucbvax!SNYCENVM.BITNET!EPRF
From: EPRF@SNYCENVM.BITNET (Peter Flass)
Newsgroups: comp.os.vms
Subject: Re: Software Protection
Message-ID: <8807041734.AA23271@ucbvax.Berkeley.EDU>
Date: 1 Jul 88 15:28:51 GMT
References: 
Sender: usenet@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 27

>
>a friend of mine has a problem with his software. He wants to protect it
>against using without having his licence.
>
>There might be 3 ways for doing such a protection:
>
>- Reading the CPU identification and testing it in the program
>- ...
>
>- How can we get the cpu identification (F$GETSYI("SID")??) from within
>  the program and is this  a secure method?

  My experience has been that the SID register is *NOT* a constant, at
least on the 750.  We have had major problems with a purchased
software package which tries to use it for protection.  After several
problems the vendor finally had to send us an unprotected version.
     -Pete

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