LibraryConsensus2015Design paperCorpus record
The Bitcoin Backbone Protocol
Bitcoin Backbone. Juan Garay, Aggelos Kiayias and Nikos Leonardos.
Common prefix, chain quality and chain growth, under a synchronous network and an honest majority of hash power.
A reading of the public document. Not a copy of it, and not a claim about a later network that reused the name.
When someone says 'Bitcoin is proven secure', ask which of the three properties, under what delay, and against what fraction of hash power.
- Evidence
- Primary paper
- Re-measured
- No
- Assumptions
- 3
- Records linked
- 4
Code
Source, repository, and what is actually hosted
- ePrint 2014/765https://eprint.iacr.org/2014/765
- The source URL is not a GitHub repository. No code remote is invented.
- Full text is not mirrored. Public availability is not a licence to copy the file onto this site.
- Add to a reading list
01 Claim ledger
What the paper is allowed to say
Each row is a sentence already in the study. The status is the same on every row: a model claim, not a live measurement.
Claim 01 · Paper model
The defect
Nakamoto's paper argued informally that the longest chain is safe if most hash power is honest. This paper writes the properties you can actually prove.
Claim 02 · Paper model
The rule
Common prefix, chain quality and chain growth, under a synchronous network and an honest majority of hash power.
Claim 03 · Paper model
How it is put together
Common prefix: honest parties' chains agree except for a recent tail. Chain quality: honest blocks keep appearing in that chain. Chain growth: the chain keeps getting longer.
Claim 04 · Paper model
Where the claim stops
The model is not partial synchrony and not Byzantine quorum finality.
02 Three cuts
Observation, model, falsifier
A desk does not stop at the summary. Each claim is cut three ways, using only this study's own assumptions and checks. Nothing here is a new figure.
01 The defect
Observation
What the study says
Nakamoto's paper argued informally that the longest chain is safe if most hash power is honest. This paper writes the properties you can actually prove.
Model
What has to hold
Honest majority is an assumption, not a measurement the paper performs.
02 The rule
Observation
What the study says
Common prefix, chain quality and chain growth, under a synchronous network and an honest majority of hash power.
Model
What has to hold
Honest majority is an assumption, not a measurement the paper performs.
03 How it is put together
Observation
What the study says
Common prefix: honest parties' chains agree except for a recent tail. Chain quality: honest blocks keep appearing in that chain. Chain growth: the chain keeps getting longer.
Model
What has to hold
Honest majority is an assumption, not a measurement the paper performs.
Falsifier
What would retire it
How many confirmations sit outside the common-prefix tail?
04 Where the claim stops
03 Sequence
One action, as an operating tape
- 01The model is rounds, with a bound on how many blocks an adversary can produce.
- 02The proof tracks how often an honest party is uniquely elected.
- 03A deep confirmation is how you turn a probabilistic prefix into a decision.
- 04What fraction of hash power is assumed honest?
04 Load-bearing
The argument, and where a pitch drops it
Why it is still on the desk
The cut
When someone says 'Bitcoin is proven secure', ask which of the three properties, under what delay, and against what fraction of hash power.
Why it carries weight
If this cut is skipped, the paper's name is being used without the mechanism that makes the name mean anything.
Where it is dropped
It does not price bitcoin.
After the text
The cut
Later work relaxed synchrony and added variable difficulty. The three property names are still the right vocabulary.
Why it carries weight
If this cut is skipped, the paper's name is being used without the mechanism that makes the name mean anything.
Where it is dropped
The model is not partial synchrony and not Byzantine quorum finality.
05 Register
What has to be true
Stake and threshold · Not re-measured
The model is not partial synchrony and not Byzantine quorum finality.
Stake and threshold · Not re-measured
Honest majority is an assumption, not a measurement the paper performs.
Model · Not re-measured
It does not price bitcoin.
06 Divergence
What happened after the paper
Later work relaxed synchrony and added variable difficulty. The three property names are still the right vocabulary.
A later client, parameter set, or reward formula is a different object. Cite this paper for the mechanism. Cite a primary release for the network. This desk has not re-run the proof.
07 Pre-mortem
What to check before you use the idea
- 0 of 3 marked on this browser. A mark is a reading note, not a pass, a rating, or a recommendation.
08 Anatomy
The paper, in the order a builder needs
The problem it names
Nakamoto's paper argued informally that the longest chain is safe if most hash power is honest. This paper writes the properties you can actually prove.
What the design proposes
- Common prefix: honest parties' chains agree except for a recent tail.
- Chain quality: honest blocks keep appearing in that chain.
- Chain growth: the chain keeps getting longer.
How the mechanism is specified
- The model is rounds, with a bound on how many blocks an adversary can produce.
- The proof tracks how often an honest party is uniquely elected.
- A deep confirmation is how you turn a probabilistic prefix into a decision.
What this page does not treat as proven
- The model is not partial synchrony and not Byzantine quorum finality.
- Honest majority is an assumption, not a measurement the paper performs.
- It does not price bitcoin.
09 Lexicon
Terms, opened into the record
- Common prefix
- Honest chains match except for the last several blocks.
- Chain quality
- The adversary does not write the whole chain.
10 Repository
Every linked record on this page
Underlined words open a page that already exists: a concept, a protocol profile, a failure record, or another paper. If a word is not underlined, this desk does not have a record for it.
This is Blockchain Lab's reading of a public design paper. It is not the paper, not a copy of it, and not an offer of tokens, equity, custody or a partnership. Later network behaviour can diverge from the text. Nothing here is investment, legal or technical advice.
Research status: Design paper. Last reviewed: 1 October 2026. This is a reading of a public paper, not investment, legal or security advice.