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From: peirce@outpost.UUCP (Michael Peirce)
Newsgroups: comp.sys.mac.programmer,comp.protocols.appletalk
Subject: Re: Idea for painless copy protection
Message-ID: <0B010004.mj9ay5@outpost.UUCP>
Date: 27 Jan 91 21:31:07 GMT
Reply-To: peirce@outpost.UUCP
Organization: Peirce Software
Lines: 44
X-Mailer: uAccess - Mac Release: 1.0.3


In article <1991Jan27.144523.20674@phri.nyu.edu>, roy@alanine.phri.nyu.edu (Roy Smith) writes:
> 
> 	Second, would it be a Bad Thing for the network?  I could see how it
> might result in a flood of synchronized responses clogging the wire
> momentarily, but it wouldn't be any different than how Inter*Poll interacts
> with Responder, would it?  It would only happen once per launch, so I would
> guess that would minimize the damage.

You need to be very careful how you implement this.  I know there
are programs out there at do this (generally) already and I've heard
complaints about how they adversely affect some networks.

Keep in mind that LocalTalk networks don't really have alots of band
width to spare and can be adversely affected by lots of NBP lookup activity.

Many schemes that work for a small network fall apart for larger nets
- think about doing NBP lookups on a network with 50 different zones
or more (they're are many of these size networks out there) and waiting 
for that on every launch!

Of course if you limit this to only wreak havok at application launch
it's very easy to work around (just turn of the network while you
launch it, then turn it back on).  The more robust you make the copy
protection the more network effect you end up having.

Ther'se also the idea of a "license server" where you have the application
check in with a server that gives out permission to run and keeps
track of how many copies are running.  But then you're tied to having
a network that's up and running or the user can't even launch your
product.  It also don't control total users, just concurrent use -
very different.

There are probably some workable systems out there for this type of
thing, but please consider the consequences that your users will have
to deal with in a variety of environments.  If you make it too hard
on them they might just drop your product and switch to one that doesn't
have the disadvantages your does.

-- michael


--  Michael Peirce         --   outpost!peirce@claris.com
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