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An authenticated data structure based on a red-black tree.
Python C++ Haskell
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haskell An attempt at a haskell version
.gitignore Now with a MerkleSampler, which contains an array as well as the red-…
AGPL-LICENSE.txt Added agpl
CRAPL-LICENSE.txt Added license Summarized licenses
c_redblack.hpp Comments
c_redblack_main.cpp Insertion in LLRB tree. New zipper interface. C++ version. Simplified the redblack interface Tree dot fixed. First LLRB implementation. Header index cached in a p… Tree dot fixed. First LLRB implementation. Header index cached in a p… Tree dot fixed. First LLRB implementation. Header index cached in a p… Simplified the redblack interface

Red-Black Merkle Tree

This is a reference implementation of a Self-Balancing Merkle Search Tree (i.e., an Authenticated Data Structure [0]). This can be used to efficiently represent the essential state necessary to validate Bitcoin [1] transactions: the set of available unspent transaction outputs (UTXOs).

Authenticated Data Structures are used in protocols between three parties: 1) the trusted Source, which creates data and publishes a digest; 2) the untrusted Server, which maintains a copy of the data and responds to queries; and 3) the Client, which verifies the Server's responses against the known digest. In this implementation, the data structure requires O(N) storage and each operation takes O(log N) time. These operations can also be verified in worst-case O(log N) time using a Verification Object (a path through a Merkle tree). A verifying Client is only required to maintain O(1) state (specifically, the Merkle tree root hash).

  • RedBlack is a general purpose Red-Black binary search tree [3] that can easily be augmented with a 'digest' function. Typically, the digest should include a secure hash function, forming a dynamic Merkle tree [4].

  • a specialization of RedBlack by definining a digest/serialization protocol appropriate for Bitcoin UTXOs.

  • a script that iterates through the Bitcoin blockchain, from the genesis block to the head, incrementally updating the RedBlack as it goes (requires Gavin Andresen's python bitcointools.

  • treedot: produces graphviz illustrations of the tree (requires graphviz (dot))

  • test_redblack: unit tests for RedBlack


[0] Authenticated Data Structures. Roberto Tamassia. 2003


This software is released under the CRAPL license (appropriate for scientific use) and the AGPL license (appropriate for copyleft open source projects). If you would like a different or more permissive license, please contact me!

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