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Hashcash

Hashcash is a proof-of-work system used to limit email spam and denial-of-service attacks. Hashcash was proposed in 1997 by Adam Back and described more formally in Back's 2002 paper "Hashcash – A Denial of Service Counter-Measure". In Hashcash the client has to concatenate a random number with a string several times and hash this new string. It then has…

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Overview

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Advantages and disadvantages

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Intellectual property

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Map overview Semantic statistics

Hashcash

Nodes50
Edges49
Triples85
Avg. degree1.96
Density0.04
Components1

How this topic connects Entity context

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Hashcash

Top relations

related to References · 16
Hashcash → Adam Back, August, Ben Laurie, Combating Junk Mail, Crypto, Denial, Dwork, Naor, PDF, Pricing, Processing, Proof-of-Work' Proves Not, Richard Clayton, Service Counter-Measure, WEIS, Work
related to Email Postmark · 14
Hashcash → CSRI, Email Postmark, Exchange, Hotmail, Initiative, It, Microsoft, Microsoft's, Microsoft's Coordinated Spam Reduction, Outlook, SHA-1, The, The Microsoft, This
related to Intellectual property · 11
Hashcash → Client-Puzzles, February, IETF, In, Linux, March, RFC, RSA Security, RSA's IPR, The RFC, US7197639
related to Sender's side · 11
Hashcash → Given, Hence, However, If, It, No, Out, PC, SHA-1, The, Thus
related to How it works · 6
Hashcash → CPU, For, However, In, Receivers, The
related to Advantages and disadvantages · 4
Hashcash → Neither, On, The Hashcash, This
related to Bitcoin mining · 4
Hashcash → Bitcoin, In, Thus, Together
related to Email clients · 4
Hashcash → Mozilla Thunderbird, SourceForge, The, The Penny Post
related to Reputation · 4
Hashcash → ID, In, The, To
related to Spam filters · 4
Hashcash → However, SpamAssassin, SpamAssassin's, Support

Important terminology Word statistics

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Important terminology

hash header email time spam string number sender valid e-mail recipient's processing amount bits system proof-of-work mail spammers use zero

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Hashcashis aproof-of-work system used to limit email spam and denial-of-service attacks0.90text
Hashcashrelated to Advantages and disadvantagesThe Hashcash0.60section
Hashcashrelated to Advantages and disadvantagesNeither0.60section
Hashcashrelated to Advantages and disadvantagesOn0.60section
Hashcashrelated to Advantages and disadvantagesThis0.60section
Hashcashrelated to Bitcoin miningIn0.60section
Hashcashrelated to Bitcoin miningBitcoin0.60section
Hashcashrelated to Bitcoin miningTogether0.60section
Hashcashrelated to Bitcoin miningThus0.60section
Hashcashrelated to BlogsLike0.60section
Hashcashrelated to BlogsSome0.60section
Hashcashrelated to BlogsJavaScript0.60section

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    Min side: 3
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