Super Phones?

Excerpted from "Wired," August 1993 Playboy (Not THAT Wired)
Reprinted without Permission

Spread Spectrum technology was developed for the military to allow
for high-security communications with crystal-clear reception.  Now 
Cincinatti Microwave has introduced the Escort 9000 ($400), a cordless
digital phone with Spread Spectrum that operates on the recently
approved 900 MHz radio frequency (that's 20 times higher than the 
frequency conventional cordless phones use).  This marriage of 
technologies gives the Escort 9000 a remarkable range
of about a half maile, superior reception and complete privacy.
"Previous attempts to bring Spread Spectrum to the consumer market
have been too costly and too bulky for personal use," said
Cincinatti Microwave president Jacques Robinson, who sells the
phones directly to the public.  (Call 800-433-3487 for more
information or to order one.)  Another company, Cobra, incorporates
CM's Spread Spectrum technology into its latest 900 MHz model, and 
AT & T will introduce a 900 MHz Spread Spectrum phone in the fall.
Tropez and Panasonic also offer 900 MHz phones (without Spread
Spectrum).  It is rumored that the range for some 900 MHz phones
could be increased in the future to up to seven miles, which means 
that one could serve as an around-town alternative to a cellular
phone.

---END EXCERPT

Now, here's my problem with this nice-sounding product.  I called
the 800 number to ask for an explanation of this product, which
immediately aroused my suspicion.

From my conversation with the receptionist on the other end
of the phone, which was somewhat less than informative, the
idea of Spread Spectrum technology is that the signal is
spread out into individual packets on different wavelengths,
then reconstituted at the other end, using some sort of session
key generated at the beginning of each transaction.

Considering the rather lax security of high-ranking government
and military officials with phone technology, recent eavesdropping
on Air Force One and the White House most glaringly, I find
it difficult to accept as kosher any security scheme created
by the government and then offered to private industry.

More chillingly, the receptionist told me that no one would be
able to perform surveillance on me "except the government."

Alerted to this possibility, I immediately asked whether it 
had the Clipper Chip or the Capstone, or whether there was some
sort of key escrow involved.

This got me put on hold for a couple minutes.

Then the receptionist returned, and told me that the person from
the engineering department who took care of the phones had indicated
that not even the government had the technology to monitor these
phones.

Upon asking how and why the government might do this, I received
a rather chilly notification that the engineering department,
was, of course, unwilling to reveal these secrets.  Well, it was
worth a try.

I gave them my address so that they could send me further information.

More reports forthcoming.

You can contact Cincinatti Microwave by telephone at:
(800) 433-3487

or by snailmail at:

Cincinatti Microwave
1 Microwave Plaza             
Cincinatti, OH 45249
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"Spread spectrum" does *not* imply "encrypted". The spreading
sequences are quite often just simple linear feedback shift registers,
which anyone with basic knowledge of cryptanalysis knows how to crack.

Anyone with knowledge of the signal format and the right hardware
could easily intercept such a signal. This *definitely* includes the
government.

The fact that spread spectrum usually thwarts the average scanner
enthusiast is actually rather unfortunate in my opinion, because that
lessens the demand for truely secure cryptography.

Phil

> Now, here's my problem with this nice-sounding product.  I called
> the 800 number to ask for an explanation of this product, which
> immediately aroused my suspicion.
> 
> >From my conversation with the receptionist on the other end
> of the phone, which was somewhat less than informative, the
> idea of Spread Spectrum technology is that the signal is
> spread out into individual packets on different wavelengths,
> then reconstituted at the other end, using some sort of session
> key generated at the beginning of each transaction.

Essentially this is correct, but as Phil Karn already pointed out... spread
spectrum is easy to de-spread.

However, Motorola has a cordless phone called the Secure Clear phone that
operates at 46 to 50 MHz (standard cordless phone freqs.) that has 
"encryption" between the handset and the base.

After calling motorola I am not impressed... they use frequency inversion.
Their support person stated that the goal is to "stop casual eavesdroppers 
that might use baby-monitors or police scanners."  Which is fine and good.
I know, from personal experience, the problems that can arise from cordless
telephones being monitored and the information used against a person.

The Motorola and Cincinatti Microwave phones can help with the casual listeners
that are out there (and there are quite a few of them!), but neither will
stop an interested party with resources to spare.  :)

-- 
"I'm not being irrational, I just know to much."  - Tim Allen
--
Pat Hykkonen, N5NPL                     Texas State Technical College at Waco
Internet: {pat,postmaster,root}@tstc.edu       Instructional Network Services
Packet: N5NPL@WD5KAL.#CENTX.TX.USA.NA        3801 Campus Dr.  Waco, Tx  76705
Public keys available! ** 1984 + 10 **     V:(817) 867-4830  F:(817) 799-2843