From: tallpaul@pipeline.com (tallpaul)
Date: Tue, 26 Dec 1995 04:06:04 +0800
To: Adam Shostack <adam@lighthouse.homeport.org>
Subject: Re: Only accepting e-mail from known parties
Message-ID: <199512251933.OAA14735@pipe8.nyc.pipeline.com>
MIME-Version: 1.0
Content-Type: text/plain


How about one-time electronic stamps. 
 
I generate a large-ish number of long-ish random numbers. 
 
I store these into a data base on my system. 
 
I send one e-stamp to all of the people I want to communicate with and vice
versa. 
 
Each person uses the e-stamp in the header or some other area of their
message to me easily accessible to my mail bot. 
 
My bot reads the e-stamp and then checks the data base to see if the stamp
is valid. 
 
If not, then /dev/null. If so, then: 
 
     a) send the message to me; 
     b) delete the used e-stamp from the data base; 
     c) send a confirmation of received message with a new e-stamp in it. 
 
Thoughts? (I see one problem with this but it should be able to be worked
out once the basic method is agreed to). 
 
--tallpaul