# Information Security and Cryptography Research Group

## Special Aspects of Escrow-based E-Cash Systems

### Lennart Meier

Master's thesis, Universität des Saarlandes, Saarbrücken, 2000.

Electronic cash systems are one way to implement digital payments; e-cash schemes can offer user anonymity at the same level as paper-based cash. However, this anonymity can be misused for illegal purposes; therefore, some means to revoke the anonymity under specific circumstances seems desirable. Many “escrow-based” schemes have been proposed; the information needed for this is usually escrowed at a trusted third party. In this thesis, we'll take a close look at various escrow-based e-cash schemes and investigate their security for all participants and the assumptions it is based on. The notion of “self-escrowing”, i.e. replacing the trusted third party by the user himself, will be addressed; finally, by combining some of the techniques presented, we construct an escrow-based e-cash scheme which offers strengthened security against forgery of coins.

## BibTeX Citation

@mastersthesis{Meier00,
author       = {Lennart Meier},
title        = {Special Aspects of Escrow-based E-Cash Systems},
year         = 2000,
month        = 3,
school       = {Universität des Saarlandes, Saarbrücken},
}