- cypherpunks-legacy@lists.ogf.org

RE: 'Sunday Times' article on GSM changes
by DrZaphod 06 Feb '93

06 Feb '93

In Message Fri, 5 Feb 93 13:14:58 EST, phantom.com!thug(a)netcomsv.netcom.com (Murdering Thug) writes: >According to what I read it seems that the whole issue of cellular radio >signal encryption is really a non-issue. They could have the most secure >standard for radio signal encryption and it wouldn't matter. The FBI >already uses tie lines and REMOBs (remote observation units) at the telephone >switching centers to access the conversation on any particular local loop >(phone number) that they want. The reason cells are encrypting is to protect against "unauthorized persons" [i.e civilians who havn't joined the fedz and DON'T live off other people's money [ours]]. I think this is another case that shows: letting other people encrypt your data for your protection never works out to be much good. I agree with Thug in that we need to employ our OWN encryption from one end to the other. That CRYPTOCUP soundz pretty good right about now. TTFN! DrZaphod [AC/DC] / [DnA][HP] [drzaphod(a)ncselxsi.uucp] Technicolorized

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RE: 'Sunday Times' article on GSM changes
by Eric Fogleman 06 Feb '93

06 Feb '93

(Thug writes) > According to what I read it seems that the whole issue of cellular radio > signal encryption is really a non-issue. They could have the most secure ... > What makes you think they don't have the same kind of REMOB/BLV capability > to the cellular telephone switches? I mean, if a conversation is scrambled ... If getting around GSM encryption is no problem, then why are governments pushing the issue? Eric Fogleman

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CELP speech compression code at cygnus.com:/pub/celp.speech.tar.Z
by gnu 06 Feb '93

06 Feb '93

The code is up for FTP where you-all can get it. I made both compressed and gzip'd versions (gzip gives smaller files than compress, is faster to decompress, but slower to compress). -rw-rw-r-- 1 gnu cygnus 2571835 Feb 5 16:04 celp.speech.tar.Z -rw-rw-r-- 1 gnu cygnus 2099441 Feb 5 16:09 celp.speech.tar.z Much of the tar file is samples of compressed and uncompressed speech, (used for testing the code). The actual C code is about 340K uncompressed, and there's also a Fortran version in there. I have a copy of the actual compression standard, but not online. The Information Liberation Front is welcome to a copy -- maybe I should just leave it on the table at the next meeting and hope someone "anonymously" picks it up and scans it in. It's public domain, so there's no special thrill from liberating it. John

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hardware scramblers
by deboni＠diego.llnl.gov 05 Feb '93

05 Feb '93

I don't know a whole lot about this subject, but I'd like to hazard a suggestion about hardware scramblers. I once upon a time saw an article in some source, perhaps Popular Science or the like, on how to build a cheap voice scrambler for telephones using a circuit called a ring demodulator (or something like that). The curcuit had a ring of diodes, looking like a bridge rectifier, with the voice and noise source feeding in and some function of the inputs feeding out. The idea was to pick a radio station at random, use its audio as a noise source, and let your partner at the other find the station that renders the signal comprehensble. This only works if both parties have access to the same radio signals, and can easily be defeated in short order by any eavesdroppers with radios, but taping your conversation does them no good. Further, it's cheap, requires no compression or sophisticated hardware, and uses the whole telephone voice bandwidth. I've never tried this, so I don't know how well it works, but since it's an old idea, perhaps it could be dressed up for modern needs. Tom DeBoni deboni(a)llnl.gov

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Re: `Sunday Times' article on GSM changes
by pmetzger＠shearson.com 05 Feb '93

05 Feb '93

> From: Brad Huntting <huntting(a)glarp.com> > > It would seem that both the sender and reciever need to be exactly > syncronized to within 1/4 of a bit for this to work. Since voice > data requires about 64Khz Just as a point of information, you can compress voice into 4kbit/sec without any real loss of quality. Perry

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Re: `Sunday Times' article on GSM changes
by crunch＠netcom.com 05 Feb '93

05 Feb '93

Gilmore writes: >Anyone interested in beating him to the net with something that >would compress voice (or voicemail) in realtime on a 486 or a SPARC? I used to build voice scramblers, but mostly in hardware using a Psuedo noise source. It wirked pretty good, but had to compress the bandwidth down to about 2kHz. Thus the reason why it sounds like talking in a tunnel. Has anyone done a feasability study on whether of not a 486 or Sparc station can do this in real time? It would seem to me that Voice mail systems should incorperate this in their system, thus scrambling the messages unless a access code can be used to retrieve it. JD

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RE: 'Sunday Times' article on GSM changes
by crunch＠netcom.com 05 Feb '93

05 Feb '93

>What makes you think they don't have the same kind of REMOB/BLV capability >to the cellular telephone switches? I mean, if a conversation is scrambled >from the mobile phone to the switch over the radio, it must be unscrambled >at the switch before it can be transmitted over the trunk lines into the >PSTN network, and that's where the FBI places their tie-lines and REMOB >units. As far as I know, most cellular interfaces to the BOC system is digital. But I suppose there might be some interface somewhere. I'll put a few "feelers" out and see what I come up with. JD (Scuse line noise..)

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A Bug?
by crunch＠netcom.com 05 Feb '93

05 Feb '93

Don't know if it's something stupid I'm doing, or if there's a bug in the Mac PGP 2.1, but after selecting Text only, and Radix 64 mode, after encrypting the text, I lose all carriage returns after decrypting it. Almost everything I get had no carriage returns in it. I use the Think C editor, or BBEdit for editing my text. Is there an option that permits PGP to retain the carriage returns? JD

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Dear Mr. President
by deltorto＠aol.com 05 Feb '93

05 Feb '93

Here are a few thoughts on the letter we will send to Bill. [A] We should make up a key for the whole group with an insanely long password and all get together and sign it in person. [B] We should send our message to Bill _heavily_ encrypted and as anonymously as possible (I'm talkin' to you remailer studs), and we should send the key under a separate 'envelope.' I suggest that this will definitely get the White House's attention (probably a lot of other people at the No Shit Association too, but hey...). [C] Beyond a congratulatory notes that he has actually bothered to take the Presidency "online," the letter might focus on two main areas: 1. Technology/Privacy: - Privacy and how important it is to the preservation of Democracy. Mentioning the White House email situation to bring it home. - Advancement of technology and how the Government can support us by getting the fuck out of the way and/or providing R&D support (hear, hear, Crunch). I.e let's get those data highways rolling along. - How we feel about the various Intelligence Services of the US Government and how taming them might improve our international reputation. And tell them not to fuck with our mobile phones, etc. Politics: We might also mention how nice it is that he supports Family Values (unlike Bush and rich Cronies), how savvy he is to leave gays in the military alone (unlike most of the GI's I have ever heard of, who mercilessly harrass women), what a good thing it is to house homeless people in unused military barracks and how important it is to send aid to Russia before they come over here and try to live in our unused military barracks, stuff like that. [D] Let's make it a nice letter, full of support, good vibes and humor. We are an interesting group of engineers, artists and creative people and he should be reminded that we are watching him and that he has some support. The guy has a tough job cleaning up all the shit the Bushmen left behind. He deserves some goodwill. [E] ? dave

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RE: 'Sunday Times' article on GSM changes
by thug＠phantom.com 05 Feb '93

05 Feb '93

According to what I read it seems that the whole issue of cellular radio signal encryption is really a non-issue. They could have the most secure standard for radio signal encryption and it wouldn't matter. The FBI already uses tie lines and REMOBs (remote observation units) at the telephone switching centers to access the conversation on any particular local loop (phone number) that they want. I know, because in my younger days as a phone phreak my friends and I used to play with REMOBs and BLV all the time, so I personally know that they exist. What makes you think they don't have the same kind of REMOB/BLV capability to the cellular telephone switches? I mean, if a conversation is scrambled from the mobile phone to the switch over the radio, it must be unscrambled at the switch before it can be transmitted over the trunk lines into the PSTN network, and that's where the FBI places their tie-lines and REMOB units. Like someone else in this thread already mentioned, high-level end-to-end encryption is the only way to protect your privacy. Thug

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