From: dwa@mirage.svl.trw.com (Dana Albrecht)
Date: Mon, 21 Nov 94 19:51:27 PST
To: cypherpunks@toad.com
Subject: Re: Admiral Inman
Message-ID: <9411220351.AA01231@mirage.svl.trw.com>
MIME-Version: 1.0
Content-Type: text/plain



> 
> From owner-cypherpunks@toad.com Mon Nov 21 17:49:07 1994
> Date: Mon, 21 Nov 94 20:17:47 EST
> From: wcs@anchor.ho.att.com (bill.stewart@pleasantonca.ncr.com +1-510-484-6204)
> To: pcw@access.digex.net
> Subject: Re: Admiral Inman
> Cc: cypherpunks@toad.com
> Sender: owner-cypherpunks@toad.com
> Content-Length: 1071
> 
> Peter Wayner writes:
> > I've always assumed that the excitement behind the Digital Telephony
> > bill was to go after VoicePGP. 
> 
> Not really - Digital Telephony goes after the phone companies,
> not the end users, which makes it easier for the government to impose.
> Among other people it *is* going after are cellphone companies which 
> are getting a lot of pressure to include encryption on their radio links
> (some people are pressuring them to use *real* encryption, the NSA has
> been pressuring them to use at most wimpy encryption, and some people have
> been pressuring them to put in _anything_, even rot-13, just so there's
> _some_ vague privacy protection out there.)
> It's also, of course, going after carriers who have the _gall_ to use 
> more powerful telephone systems than the FBI can afford to crack :-)
> 
> Now, VoicePGP may be the next step in banning things - after all,
> they could declare use of cryptography to be Probable Cause that 
> you're conspiring about something, which would let them confiscate your
> computer equipment and make you sue to get it back.
> 
> 		Bill
> 


Check out:

	TIA/EIA Telecommunications System Bulletin
	Cellular Radiotelecommunications Intersystem Operations:
	Authentication, Signaling Message Encryption and Voice Privacy
	TSB51

Their idea of "Voice Privacy" is to repeatedly XOR a 260 bit session key
with the data stream.  I quote:

	8.2.47  VoicePrivacyMask (VPMASK)

	This parameter contains a 528-bit field consisting of two 260-bit masks
	used for voice privacy on a digital traffic channel.  One mask is for
	speech transferred in the inward direction (from the CSS toward the MSC)
	and one is for speech transferred in the outward direction (from the MSC
	toward the CSS).  These masks are calculated using CAVE parameters in
	effect when the call is established and remain constant for the duration
	of the call.

So, while analog calls are not encrypted, you can look forward to COMPLETELY
SECURE (sarcasm) digital transmission.

Wonder how much the Gov'mint bribed the phone companies for this stunt...

Dana W. Albrecht
dwa@mirage.svl.trw.com