Live briefing
Everything about Hashcash
System for dealing with email spam
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 to do so over and over until a hash beginning with a certain number of zeros is found. Wikipedia →
🧠Start here: a 6-step reading path
- Read the overview: HashcashA 5-minute orientation
- Read the landmark paper: Hashcash Tree, a Data Structure to Mitigate Denial-of-Service AttacksCited 3 times
- Go sideways: Proof of workA closely related topic
- Go sideways: DKIMA closely related topic
đź“– Definitions
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🗂️ The subject at a glance
🏆 Landmark papers (most cited)
đź“š Books worth reading
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đź”— Related topics
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