"Arnold G. Reinhold" <[EMAIL PROTECTED]> wrote: > The Army actually has a training course (from 1990) on-line that > describes such a system in detail. The cipher system, called DRYAD is > covered in > https://hosta.atsc.eustis.army.mil/cgi-bin/atdl.dll/accp/is1100/ch4.htm > .
Your description fits, it sounds like DRYAD. <rest of good post, snipped, except:-> > >Consider these difficulties: it was *banned* > >to use any form of comsec that wasn't centrally > >approved. No personal code words, no CB radios, > >no knicknames, no nothing... (In practice there > >was some leakage, I recall on my last exercise, > >logistics back to the battalion HQ in the city > >was handled over a cellular phone!) > > I wonder if such bans are intended to make sure the military can read > the traffic of its own soldiers as much as they are to protect > against enemy exploits. :-) The reason was that sigint on the other side could note particular differences from standard procedure, and use that to track units up and down the front. For the same reason, all plan names are generated randomly, from a dictionary program in HQ; sigint people could derive a lot of clues from the personally picked plan names. (Hence you can always tell when the professionals have lost control, as the plan names become political.) iang --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]