Privacy/Online Commerce - Digital Money & Transactions

David Chaum's August 1992 article from Scientific America describing "blind signature' technology and the possibilities of enhanced digital privacy and electronic cash.
a 1994 list of publications by David Chaum, founder of DigiCash, and pioneer of most of the ideas surrounding digital money.
DigiCash press release about the testing of it's Ecash software
a 1994 brochure describing DigiCash's electronic payment systems.
October 1993 paper attempting to describe Chaum's digital cash in lay terms, and outlining how Chaum avoids the notorious "double-spending" problem. Followed by other online articles and commentary.
may 1994 description of Magic Money V1.1 with autoclient and multiserver capability (a recent idea competing with Chaum's Ecash)
"Digital Cash and Monetary Freedom", Jon W. Matonis, Presented at INET '95, Internet Society Annual Conference, Honolulu, Hawaii, June 26-30, 1995. This paper describes the differences between mere encrypted credit card schemes and true digital cash, which presents a revolutionary opportunity to transform payments. The nine key elements of an electronic, digital cash are outlined and a tenth element is proposed which would embody digital cash with a non-political unit of value.
a listing of online banks worldwide, books about online banking and a description of why online banking increases the privacy of individuals.
Chaum's 1993 article describes 3 ways to make online cash exchange work.
Chaum's 1994 paper explaining the technique of prepaid smartcards which contains stored value (in terms of dollars) which a user might exchange with a vendor rather than cumbersome cash.
"An Efficient Off-line Electronic Cash System Based on the Representation Problem", Stefan Brands, 1991. Technical paper; abstract (in part): "We present a new off-line electronic cash system based on a problem, called the representation problem, of which little use has been made in literature thus far. Our system is the first to be based entirely on discrete logarithms. Using the represenation problem as a basic concept, some techniques are introduced that enable us to construct protocols for withdrawal and payment that do not use the cut and choose methodology of earlier systems. As a consequence, our cash system is much more efficient in both computation and communciation complexity than previously proposed systems...Contrary to previously proposed systems, [our system's] correctness can be mathematically proven to a very great extent...Our system offers a number of extensions that are hard to acheive in previously known systems..." This is a gzip-compressed PostScript document.
Marc Rinquette's August 1992 article on implementing electronic cash using secure newsgroups.
"Single Term Off-Line Coins", Niels Ferguson. Technical article; abstract: "We present a new construction for off-line electronic coins that is both far more efficient and much simpler that previous systems. Instead of using many terms, each for a single bit of the challenge, our system uses a single term for a large number of possible challenges. The withdrawal protocol does not use a cut-and-choose methodology as with earlier systems, but uses a direct construction." 1991. This is a gzip-compressed PostScript file.
1994 article and commentary discussing electronic purse specifications and digital cash.

Related Topics

Anonymity/pseudonymity issues Archives
Good background material.
Encryption topics Archive
link to directory of info on general (usually technical) encryption topics. Good background material.
Digital Signatures Archive
link to directory of info regarding the related technology of digital signature and electronic authentication. Good background material.

Links to Related Off-Site Resources

David Chaum's DigiCash support site
There's also an alternate site
Digicash provides it's own "Ecash" applications, but others have used Chaum & DigiCash's techniques.
a Chaumian DigiCash system by C2Net [Defunct; link to no longer functions.]
Mondex Digital Transaction System Info Pages
CyberCash secure Internet payment system pages.
a European Comission funded project to look into the implications of and to develop systems to trade intellectual properties over networks. This will also encompass payment systems and methods of identifying the owners of intellectual properties and media. There are questionairres on the web site which people can fill in to help us set precedents and build consensus on sensitive issues in copyright.