From: Bill Stewart <stewarts@ix.netcom.com>
Date: Sat, 12 Aug 95 01:59:55 PDT
To: "Vladimir Z. Nuri" <vznuri@netcom.com>
Subject: Re: PRZ encrypted voice software release imminent
Message-ID: <199508120857.BAA11361@ix5.ix.netcom.com>
MIME-Version: 1.0
Content-Type: text/plain


At 10:59 AM 8/11/95 -0700, you wrote:
>the requirements for live voice encryption are pretty significant:
>a fast computer and fast modem. this alone is only a subset
>of those people using PGP right now. 

The tradeoffs are speech encoding quality, and we basically crossed that
line a year or two ago for the high end, and are heading toward mass capability.
9600 baud high-quality speech takes lots of crunching, 13.3 kbps GSM takes
a Sparc 2 or maybe a Pentium, 16 kbps ADPCM is dirt trivial and can probably
run on an 8086.  The coding options with Nautilus run on 386s.
And you can get by with less if you're willing to put up with half-duplex.

Yes, lots of us aren't using modems faster than 14400 now, but you can get a 
14.4/19.2 modem at Fry's for well under $100.  (19.2 is unfortunately
not quite enough to 16 kbps, given start and stop bits, unless you do
synchronous
or start playing with V.42 a bit, but it's close.  Sound cards are down in
the $50 range,
and give you the analog/digital conversion as well as some computation.
Adding a sound card is a bit of work, given the wonderful operating systems
on many PCs :-), but folks put them in along with CDROMs so they can run
all the latest multimedia applications, or high-end versions of DOOM.

Anybody who needs to avoid government or business-competitor eavesdroppers
can probably
afford $150 in extra hardware for their PC.

This doesn't apply to international communications or folks in the boonies,
where it's hard to get full performance out of modems, so you Commie
spies and Earth First!ers will need more expensive high-tech equipment :-)...
#---
#                                Thanks;  Bill
# Bill Stewart, Freelance Information Architect, stewarts@ix.netcom.com
# Phone +1-510-247-0664 Pager/Voicemail 1-408-787-1281
#---

Storyteller makes no choice - soon you will not hear his voice.
His job was to shed light, and not to master.      RIP, Jerry