[GreenKeys] Here's a sweet one on the bay.

[COURYHOUSE at aol.com]

some of these  sellers  like to throw a lot of  terms  around  to look 
educated and make the listing  look    authoritative.... . many times if  you 
try to explain to them how it  was  they  just  argue!  weird?  Yea! 
 
----Ed#
 
 
In a message dated 5/17/2013 7:06:18 A.M. Mountain Standard Time,  
captainkirk359 at gmail.com writes:

On 17  May 2013 00:38, Jeffrey D Angus <jdangus at att.net> wrote:
> On  5/16/2013 10:41 PM, hwhall at compuserve.com wrote:
>
> "The US Army  Signal Corp's teletype typewriter... was the US equivalent 
to
>  the
>
> famous German enigma machine. "
Oh Lord I didn't even  *SEE* that on the eBay page; I think I'm going
to die laughing at the  person's sheer ignorance.


> Typical sequence was:
> 1.  generate secret message in plain text.
> 2. use crypto machine to  convert to secure text.
> 3. send secure text via teletype  machine.
> 4. receiver secure message via teletype machine.
> 5.  decode message with crypto machine.
> 6. hand secret message in plain  text to the person that needed it.
>
And if you were a  Nazi^H^H^H^HGerman in the Luftwaffe, you would have done 
it:
1. Generate  (plaintext) message.
2. Turn on T-52 Geheimschreiber, and transmit  enciphered message.
3. Receive decrypted mesage on the other end's T-52  Geheimschreiber.
4. Give message to Luftwaffe officer for whom it was  destined.
(5. Shortly afterward in Bletchely Park, the British are reading  the
exact same message.)

Because the T-52 didn't have any facility  for tape operation, that's
how BP were able to get into the T-52d and T-52e  versions of the
machine. Because when one operator had to rerun a message,  the British
saw that was going on in that circuit... and then the operator  took
some liberties in the re-run plaintext (a few more  abbreviations),
which resulted in the ciphertexts/plaintexts being somewhat  different.
But different in such a way that they could determine both what  the
plaintext was, and the function of the T-52d.

The Lorenz SZ-4x  machines on the other hand were more smartly
designed. Though BP still got  into "Tunny"... in fact we can thank the
SZ-4x machines for causing the  construction of one of the first
computers (COLOSSUS).


> Two  examples of the machines used by "our side" (The US) during
> World War  II.
> The M-209. Secure enough for most time sensitive stuff.
>  <http://www.cryptomuseum.com/crypto/hagelin/m209/index.htm>
It's good  for tactical uses, but still has its issues. Being that it's
really not  that strong. However, it was excellent in terms of theatre
level messages  (since by the time the Germans and/or Japanese would be
reading the  plaintext, the Allied forces would already have
begun/finished whatever  they were ordered ("Hallo Fritz? Ve have the
plaintext! The Allies vill be  attacking ze Gruppe North." "VE KNOW
THAT ALREADY! VE HAVE KNOWN THAT SINCE  THEY STARTED ATTACKING, THREE
HOURS AGO!" "Oh?  Scheiße...")).


> And the SGIABA for stuff that needed to STAY  secret.
>  <http://www.cryptomuseum.com/crypto/usa/sigaba/index.htm>
>
Well,  SIGABA message did *STAY* secret... until 2003, when Michael  Lee
cryptanalysed it for his master's thesis at UC Santa Barbara. And  then
Heather Kwong did it again at San Jose State University in  2008,
shortly after Mark Stamp and Wing On Chan did it for a  Cryptologia
article in  2007...

Cheers,
Christian
______________________________________________________________
GreenKeys  mailing list
Home:  http://mailman.qth.net/mailman/listinfo/greenkeys
Help:  http://mailman.qth.net/mmfaq.htm
Post:  mailto:GreenKeys at mailman.qth.net

2002-to-present greenkeys archive:  
http://mailman.qth.net/pipermail/greenkeys/
1998-to-2001 greenkeys archive:  
http://mailman.qth.net/archive/greenkeys/greenkeys.html
Randy Guttery's  2001-to-2009 GreenKeys Search Tool:  
http://comcents.com/tty/greenkeyssearch.html

This list hosted by:  http://www.qsl.net
Please help support this email list:  http://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20130517/0d4cf3f9/attachment.html>