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LibraryStorage and networks2002Design paperCorpus record

Kademlia: A Peer-to-peer Information System Based on the XOR Metric

Kademlia. Petar Maymounkov and David Mazières.

Nodes have identifiers. Distance is XOR. Each node keeps contacts in buckets by distance, and a lookup walks toward the target in logarithmic steps.

A reading of the public document. Not a copy of it, and not a claim about a later network that reused the name.

A network that says DHT should say which distance, which bucket size, and what a lookup returns when the closest peers are all the attacker.
Evidence
Primary paper
Re-measured
No
Assumptions
3
Records linked
2

Code

Source, repository, and what is actually hosted

  • Maymounkov and Mazièreshttps://pdos.csail.mit.edu/~petar/papers/maymounkov-kademlia-lncs.pdf
  • 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.

  1. Claim 01 · Paper model

    The defect

    Finding a node in a large network by flooding does not scale. The lookup has to have a shape.

  2. Claim 02 · Paper model

    The rule

    Nodes have identifiers. Distance is XOR. Each node keeps contacts in buckets by distance, and a lookup walks toward the target in logarithmic steps.

  3. Claim 03 · Paper model

    How it is put together

    XOR is a metric. It is not a security claim. Buckets are replacement caches of peers. The paper is about lookup, not about paying for storage.

  4. Claim 04 · Paper model

    Where the claim stops

    Kademlia does not authenticate the data.

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.

  1. 01 The defect

    Observation

    What the study says

    Finding a node in a large network by flooding does not scale. The lookup has to have a shape.

    Model

    What has to hold

    Kademlia does not authenticate the data.

    Falsifier

    What would retire it

    Does a lookup authenticate the record, or only find a peer?

  2. 02 The rule

    Observation

    What the study says

    Nodes have identifiers. Distance is XOR. Each node keeps contacts in buckets by distance, and a lookup walks toward the target in logarithmic steps.

    Model

    What has to hold

    Eclipse and sybil attacks sit outside the happy-path proof.

    Falsifier

    What would retire it

    What is the distance function?

  3. 03 How it is put together

    Observation

    What the study says

    XOR is a metric. It is not a security claim. Buckets are replacement caches of peers. The paper is about lookup, not about paying for storage.

    Model

    What has to hold

    Many chains use the idea and change the parameters.

    Falsifier

    What would retire it

    How many peers are kept per bucket?

  4. 04 Where the claim stops

    Observation

    What the study says

    Kademlia does not authenticate the data.

    Model

    What has to hold

    Kademlia does not authenticate the data.

    Falsifier

    What would retire it

    Does a lookup authenticate the record, or only find a peer?

03 Sequence

One action, as an operating tape

  1. 01Share node ids.
  2. 02On a lookup, ask the closest known peers for closer ones.
  3. 03Stop when the closest peers have been asked.
  4. 04What is the distance function?

04 Load-bearing

The argument, and where a pitch drops it

  1. Why it is still on the desk

    The cut

    A network that says DHT should say which distance, which bucket size, and what a lookup returns when the closest peers are all the attacker.

    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

    A later client, parameter or reward formula is a different object from this paragraph.

  2. After the text

    The cut

    IPFS and Ethereum's discovery protocol are descendants. The 2002 paper is the metric.

    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

    A later client, parameter or reward formula is a different object from this paragraph.

05 Register

What has to be true

  • Data · Not re-measured

    Kademlia does not authenticate the data.

  • Cryptography · Not re-measured

    Eclipse and sybil attacks sit outside the happy-path proof.

  • Model · Not re-measured

    Many chains use the idea and change the parameters.

06 Divergence

What happened after the paper

IPFS and Ethereum's discovery protocol are descendants. The 2002 paper is the metric.

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

  4. 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

Finding a node in a large network by flooding does not scale. The lookup has to have a shape.

What the design proposes

  • XOR is a metric. It is not a security claim.
  • Buckets are replacement caches of peers.
  • The paper is about lookup, not about paying for storage.

How the mechanism is specified

  • Share node ids.
  • On a lookup, ask the closest known peers for closer ones.
  • Stop when the closest peers have been asked.

What this page does not treat as proven

  • Kademlia does not authenticate the data.
  • Eclipse and sybil attacks sit outside the happy-path proof.
  • Many chains use the idea and change the parameters.

Why the desk still reads it

A network that says DHT should say which distance, which bucket size, and what a lookup returns when the closest peers are all the attacker.

09 Lexicon

Terms, opened into the record

XOR metric
Distance between two ids is the bitwise exclusive or, interpreted as a number.
Bucket
The peers a node remembers at one range of distances.

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.

Protocols

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.