[45527] in Cypherpunks
Re: Motorola Secure Phone
daemon@ATHENA.MIT.EDU (Tatu Ylonen)
Sun Dec 17 16:55:23 1995
Date: Sun, 17 Dec 1995 13:41:05 +0200
From: Tatu Ylonen <ylo@cs.hut.fi>
To: Jyri Kaljundi <jk@digit.ee>
Cc: cypherpunks@toad.com
In-Reply-To: <Pine.SOL.3.91.951217003923.29839A-100000@sun.digit.ee>
> 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 tyyppid. Chambers yritti pitdd tuota
> nimenomaista esitelmdd jo yli vuosi sitten, mutta silloin viralliset tahot
> puuttuivat asiaan ja esitys peruttiin. Hdn on lvytdnyt algoritmista aukkoja,
> joiden avulla purkuaika saadaan erittdin lyhyeksi.
>
> ps. ne meistd, jotka pddsevdt mboneen kdsiksi, voivat seurata tapahtumia
> livend :)
[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
