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Edge Cases: The Metanet Blog

Part 2 — The Metanet Protocol

Part 2 — The Metanet Protocol

In the last post I was careful to make the distinction between the Metanet as a concept and the Metanet protocol.

  • 2.2 — Domains, naming & locating
  • 2.3 — The Metanet & existing protocols
  • 2.4 — Data insertion and transaction structure

Directed Acyclic Graphs (DAGs)

  • Acyclic — contains no cycles.
  • Graph — comprises nodes and edges.

Blockchain DAGs

The blockchain, as specified by the Bitcoin white paper, is a DAG. It is remarkable how often this observation is either misinterpreted or missed entirely as a property of the proof-of-work blockchain. It is not uncommon to find articles ‘comparing’ blockchains and DAGs as if they were alien concepts — which could not be further from the truth.

  1. the Transaction DAG.

The Block DAG

As I’m sure virtually all readers are aware, the blockchain, under its simplest possible description, is a chain of cryptographically linked blocks of data. The data in each block in-turn comprises a block header and a set of transactions, but when viewing them through the lens of graph theory, we will only consider the entire block of data as a discrete object – without breaking it up further into its components.

Bitcoin: A Peer-to-Peer Electronic Cash system [9]

The Transaction DAG

In each block of the blockchain, there is a set of transactions, which are collectively represented by a Merkle root included as part of the block header for the respective block. In other words, the transactions in a block are effectively also an input to the cryptographic hash used to create edges between blocks in the blockchain.

  • Out-degree — the number of edges pointing out of a node.

The Metanet Graph

Why use a DAG?

There are a number of inherent properties of directed graph structures which lend themselves ideally to the use cases for Internet-like data. We will go through more in some detail next time, but some of them can be listed here:

  • Searchable;
  • Flexible; and
  • Native.

Co-existing Graphs

As a final thought for today’s post, I want to draw your attention to how the transaction DAG and the Metanet graph will intertwine and co-exist.

Resources

The following resources will be useful as supporting material for the blog series in general:

  1. _unwriter’s explanation of the Metanet.
  2. Metanet slides from CoinGeek Toronto (2019).
  3. The Genesis Metanet tree: graph, thread.
  4. The MetaWriter tool: github, thread.
  5. Metanet planaria.

Copyright

© 2019 nChain Limited. All rights reserved. This article is provided without any warranties whatsoever and shall not result in the grant of any license, whether implied or otherwise. nChain Limited shall not be liable in any way for the use of the information provided herein.

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