Date: Sun, 8 Oct 1995 14:20:27 -0700 (PDT) From: Wei Dai <weidai@eskimo.com> Now if the bank allows this exchange of old coins for new coins to be done over an anonymous network (e.g., a remailer-net), then the system is anonymous as long as you don't move physical money in or out of the system. Maintaining anonymity when moving physical money in and out of the system is what blinding helps you to do, but this will be less useful in a fully digital economy where such movement will be infrequent. See: Gennady Medvinsky and B. Clifford Neuman. NetCash: A design for practical electronic currency on the Internet. In Proceedings of 1st the ACM Conference on Computer and Communication Security November 1993. For a discussion of the tradeoffs for this weaker form of anonymity. You can find postscript for this paper as: ftp://prospero.isi.edu/pub/papers/security/netcash-cccs93.ps