NODE 22ef953fMotorola Secure Phone
dan@milliways.org (Dan Bailey)Sat, 16 Dec 1995 11:57:03 +0800
I saw a new cordless phone made by Motorola in a retail outlet today
that is supposedly "Secure from eavesdroppers." I asked the
salespeople for more technical info, but they weren't very helpful.
Does anyone have any information on this? I didn't notice any "Not
for Export" stickers on the box, and the ITAR does cover
spread-spectrum technology. So is it analog or digital? Is it just
doing simple analog tricks, or is it encrypting a bitstream? Clipper
maybe? I doubt it. Any info appreciated.
Dan
***************************************************************
#define private public dan@milliways.org
Worcester Polytechnic Institute and The Restaurant at the End of the Universe
***************************************************************
NODE 5209308bRe: Motorola Secure Phone
Tatu Ylonen <ylo@cs.hut.fi>Mon, 18 Dec 1995 14:35:04 +0800
> What about cellular phones, especially GSM? As I have heard GSM is
> supposed to be secure, at least thats what the salespersons tell every
> time they are selling a GSM.
>
> I know ciphering algorithms A3, A8 and A5 are used in GSM phones, but I
> know nothing more about them.
I got the following from mjos@math.jyu.fi a couple of months ago.
Unfortunately I was unable to attend or listen on mbone. Does anyone
know more about this?
> University of Cambridge Computer Laboratory
>
> SEMINAR SERIES
>
>
> 10th October Bill Chambers, King's College, London
> PROBLEMS OF STREAM CIPHER GENERATORS WITH MUTUAL CLOCK
> CONTROL
>
> ..
> GSM:n salausalgoritmi on juuri tuota tyyppi. Chambers yritti pit tuota
> nimenomaista esitelm jo yli vuosi sitten, mutta silloin viralliset tahot
> puuttuivat asiaan ja esitys peruttiin. Hn on lytnyt algoritmista aukkoja,
> joiden avulla purkuaika saadaan erittin lyhyeksi.
>
> ps. ne meist, jotka psevt mboneen ksiksi, voivat seurata tapahtumia
> liven :)
[Free translation: The GSM encryption algorithm is of exactly that
type. Chambers tried to have this particular presentation over an
year ago, but at that time the official side interfered and the
presentation was cancelled. He has found holes in the algorithm that
can be used to make decryption (without key) very quick.
PS. Those of us who can get access to mbone, can follow it live.]
Tatu
NODE cfc314e5Re: Motorola Secure Phone
Piete Brooks <Piete.Brooks@cl.cam.ac.uk>Sun, 17 Dec 95 14:33:43 PST
> I got the following from mjos@math.jyu.fi a couple of months ago.
> Unfortunately I was unable to attend or listen on mbone. Does anyone
> know more about this?
Yes -- we have analogue A/V on a VHS cassette, digital MBone recording on M/O,
and an abstract ... see below.
>> University of Cambridge Computer Laboratory
>> SEMINAR SERIES
>> 10th October Bill Chambers, King's College, London
>> PROBLEMS OF STREAM CIPHER GENERATORS WITH MUTUAL CLOCK CONTROL
>> GSM:n salausalgoritmi on juuri tuota tyyppi. Chambers yritti pit tuota
>> nimenomaista esitelm jo yli vuosi sitten, mutta silloin viralliset tahot
>> puuttuivat asiaan ja esitys peruttiin. Hn on lytnyt algoritmista aukkoja,
>> joiden avulla purkuaika saadaan erittin lyhyeksi.
>> ps. ne meist, jotka psevt mboneen ksiksi, voivat seurata tapahtumia
>> liven :)
> [Free translation: The GSM encryption algorithm is of exactly that
> type. Chambers tried to have this particular presentation over an
> year ago, but at that time the official side interfered and the
> presentation was cancelled. He has found holes in the algorithm that
> can be used to make decryption (without key) very quick.
> PS. Those of us who can get access to mbone, can follow it live.]
<TITLE>Security Group Seminar, 10th October 1995</TITLE>
<H1>Security Group Seminar, 10th October 1995</H1>
<HR>
<DL>
<DT>Speaker:
<DD>Bill Chambers, King's College, University of London<P>
<DT>Date:
<DD>Tuesday 10th October<P>
<DT>Place:
<DD>Room TP4, Computer Laboratory<P>
<DT>Title:
<DD>PROBLEMS OF STREAM CIPHER GENERATORS WITH MUTUAL CLOCK CONTROL<P>
</DL>
The speaker has been looking at the cycle structure of an algorithm
posted just over a year ago on the Internet and alleged to be the
secret A5 algorithm used for confidentiality in the GSM mobile
telephone system. This algorithm employs three mutually
clock-controlled shift registers, and can fairly quickly enter a
loop with what is essentially the shortest possible period, a
number very small compared with the total number of states, or even
its square root. Moreover this behaviour is robust, not being
influenced by factors such as choice of primitive feedback
polynomial or even clocking logic (with a proviso to be
discussed). A fairly straightforward explanation for this
behaviour has been found. Some ways of getting around the problem
of excessively short periods are considered, as well as the
behaviour of systems with different numbers of mutually clocked
registers. In particular a mention is made of the wartime T52e
cipher, perhaps the inspiration for "alleged A5".<P>
NODE 1e48142fRe: Motorola Secure Phone
sameer <sameer@c2.org>Sat, 16 Dec 1995 18:57:12 +0800
My AT&T 900 (or is it 9000?) MHz digital cordless phone says
the same thing. I figure it uses a weak cryptosystem. There is
something about key setup when you return the handset to the base.
(The phone was $200, FWIW)
>
>
> I saw a new cordless phone made by Motorola in a retail outlet today
> that is supposedly "Secure from eavesdroppers." I asked the
> salespeople for more technical info, but they weren't very helpful.
> Does anyone have any information on this? I didn't notice any "Not
> for Export" stickers on the box, and the ITAR does cover
> spread-spectrum technology. So is it analog or digital? Is it just
> doing simple analog tricks, or is it encrypting a bitstream? Clipper
> maybe? I doubt it. Any info appreciated.
> Dan
>
> ***************************************************************
> #define private public dan@milliways.org
> Worcester Polytechnic Institute and The Restaurant at the End of the Universe
> ***************************************************************
>
--
sameer Voice: 510-601-9777
Community ConneXion FAX: 510-601-9734
The Internet Privacy Provider Dialin: 510-658-6376
http://www.c2.org/ (or login as "guest") sameer@c2.org
NODE 7de4c869Re: Motorola Secure Phone
Jyri Kaljundi <jk@digit.ee>Sun, 17 Dec 1995 07:15:54 +0800
What about cellular phones, especially GSM? As I have heard GSM is
supposed to be secure, at least thats what the salespersons tell every
time they are selling a GSM.
I know ciphering algorithms A3, A8 and A5 are used in GSM phones, but I
know nothing more about them.
Jri Kaljundi
jk@digit.ee
Digiturg http://www.digit.ee/