Labels:text | screenshot | black and white | font OCR: Is Not Much Good but the other countries didn't feel this way, and the algorithm as now fielded is a French design, A5 is a stream cipher, and the keystream is the xor of three clock controlled registers. The clock control of each register is that A closer look at the register's own middle bit, xor'ed with a threshold function of AS GSM Encryption >From sci.crypt Fri Jun 17 17:11:49 1994 From: rja14@cl.cam.ac.uk (Ross Anderson) the middle bits of all three registers (ie if two or more of the Algorithm Date: 17 Jun 1994 13:43:28 GMT middle bits are 1, then invert each of these bits; otherwise just Newsgroups: sci.crypt,alt.security,uk.telecom use them as they are). The register lengths are 19, 22 and 23, and Subject: A5 (Was: HACKING DIGITAL PHONES) all the feedback polynomials are sparse, ...
