Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!cs.utexas.edu!ico!ism780c!haddock!kencr
From: kencr@haddock.ima.isc.com (Kenny Crudup)
Newsgroups: sci.electronics
Subject: Re: VCII
Message-ID: <13877@haddock.ima.isc.com>
Date: 28 Jun 89 17:05:55 GMT
References: <111377@sun.Eng.Sun.COM> <680@lopez.UUCP> <120@raider.MFEE.TN.US>
Reply-To: kencr@haddock.ima.isc.com (Kenny Crudup)
Distribution: na
Organization: Interactive Systems, Cambridge MA
Lines: 20

In article <120@raider.MFEE.TN.US> crc@raider.UUCP (Charles Cain) says:
>If someone is lucky enough to guess the 56 bit key, then he might think he has
>the system beat. Not quite. There are 2 modes of operation, fixed key and 
>individually addressable. Fixed key is used mostly during testing. When the
>system is fully operational, IA is used. Each uplink site that is transmitting
>scrambled material has a computer that transmits the next months key and the
>address of those descramblers authorized to receive the program. The computer
>is capable of authorizing or deauthorizing up to 2.5M descramblers a day.

Well, it seems they give you the stuff you need right there! I assume that
of course you would need to know the key at least once, but after that, hey!
A place I used to work for used to have EPROMS that would go in VCII modules
in Tracker Systems home units that replaced the original code, and would 
first lock in, and then continue to recieve programming.

-- 
Kenneth R. Crudup, Contractor, Interactive Systems, Cambridge MA
StarTrekV 3'rd favorite line: "Oh yeah?! Beam THIS up, pal!!" - D. Letterman
E-Mail, (which tends not to be delivered :-( )     Phone (617) 661 7474 x238
{encore, harvard, spdcc, think}!ima!haddock!kencr  kencr@haddock.ima.isc.com