Doubts are the ants in the pants of faith. They keep it awake and moving.
― Frederick Buechner
The Tor project was created by DARPA
(Defense Advanced Research Projects Agency) and currently receives
80% of their funding from the US Government.
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ROOTS IN THE NSANSA paper, 1996: How To Make A Mint: The Cryptography of Anonymous Electronic Cash.
CONTENTS
INTRODUCTION
1. WHAT IS ELECTRONIC CASH?
1.1 Electronic Payment
1.2 Security of Electronic Payments
1.3 Electronic Cash
1.4 Multiple Spending
2. A CRYPTOGRAPHIC DESCRIPTION
2.1 Public-Key Cryptographic Tools
2.2 A Simplified Electronic Cash Protocol
2.3 Untraceable Electronic Payments
2.4 A Basic Electronic Cash Protocol
3. PROPOSED OFF-LINE IMPLEMENTATIONS
3.1 Including Identifying Information
3.2 Authentication and Signature Techniques
3.3 Summary of Proposed Implementations
4. OPTIONAL FEATURES OF OFF-LINE CASH
4. 1 Transferability
4.2 Divisibility
5. SECURITY ISSUES
5.1 Multiple Spending Prevention
5.2 Wallet Observers
5.3 Security Failures
5.4 Restoring Traceability
CONCLUSION
REFERENCES
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An Efficient Divisible Electronic Cash Scheme
A divisible coin worth some amount of money, say $x, is a coin that can
be spent many times as long aa the sum total of all its the transactions does
not exceed $x. This property, divisibility, is very useful and convenient for a
Bit Commitment Schemes
Finally U proves to B that a value is correctly generated without revealing
committed information, by using some protocols to be described later.
To set up the commitment scheme, B generates prime P satisfying P - 1 =
2-Prime (Prime is a prime number), G and g whose orders in the multiplicative
group 25 are Prime. B sends P, G and g. U checks whether Prime = (P- 1)/2
is a prime by a probabilistic primality (or composite) test, and whether the orders
of G and g are Prime by checking that they are not 1 and GPrime E 1 (mod P)
U can commit to any integer s E Zprime by choosing R uniformly at random
and gPrime = - 1. (mod P).
in ZPrime and computing the commitment
What the fuck does this sound like? A computationally complex calculation, that anyone can easily verify, yet as it is a hash of the block other people cannot use your proof of work.
Detection of Overspending
Although, formally, the security including the detection of overspending is de-
scribed in Section 6, in this subsection, we will describe the detection procedure
of overspending.
You will shit your pants if you look at who wrote this paper:
An Efficient Divisible Electronic Cash Scheme
Tatsuaki Okamoto