the metanet - nchain · 2020. 9. 17. · planaria bitcom a.n.n.e bit:// map aip preserve sticker...

The Metanet

Jack Davies

29th May 2019

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• Introduction – the current state of the Metanet

• The Metanet Protocol:

▪ Node and edge structure

▪ Metanet-valid transactions

▪ Data-insertion methods

▪ Interpreting the graph – domains, naming and locating

• Use case examples

Contents

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“The Internet becomes a side-chain”

Credit: Ayre Media

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What do these projects have in common?

• The blockchain acts as a universal server.

• Data, websites and content are hosted on-chain.

• Everybody can contribute (e.g. Planaria).

• Specialisation.

The Metanet paradigm

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SPV check

Merkle proof

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Data storage:

Search engine:

Applications:

Identity management:

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The Metanet Protocol

The umbrella for the Metanet

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The Metanet:

“A protocol for structuring the on-chain internet”

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A transaction protocol:

• Specifies a transaction structure

• Write-permission controlled by digital signatures

• Read-permission controlled by encryption

• Highly generic

The Metanet protocol

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B://cat B:// C:// D://

Planaria Bitcom A.N.N.E bit://

MAP AIP Preserve Sticker

The Metanet protocol:

Credits: _unwriter, Mr. Scatman, Satchmo, Attila Aros, Libitx and others.

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A transaction protocol:

1. Node and edge structure

2. Metanet-valid transactions

3. Data insertion methods

4. Interpreting the Metanet:

i. Versioning

ii. Domains, naming and searching

iii. Key-management

The Metanet protocol

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Aims:

• Associate content across transactions.

• Search for content using keywords.

• Create domain-like structures.

Solution:

• Structure Metanet as a DAG.


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Definition: Directed Acyclic Graph (DAG)

• Consists of nodes and edges.


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nodes

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• Consists of nodes and edges.edges


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• Each node specifies itself and its parent.


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• Each node specifies itself and its parent.itself parent


𝑁𝑜𝑑𝑒𝑃𝑎𝑟𝑒𝑛𝑡

𝑃𝑎𝑟𝑒𝑛𝑡

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• Each node specifies itself and its parent.


𝑁𝑜𝑑𝑒


𝐶ℎ𝑖𝑙𝑑

𝑁𝑜𝑑𝑒 references 𝑃𝑎𝑟𝑒𝑛𝑡

𝐶ℎ𝑖𝑙𝑑 references 𝑁𝑜𝑑𝑒

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𝑁𝑜𝑑𝑒𝑁𝑜𝑑𝑒 = 𝐸𝑑𝑔𝑒 =

𝑁𝑜𝑑𝑒 1

𝑁𝑜𝑑𝑒 2


𝐶ℎ𝑖𝑙𝑑

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How do we achieve this structure?

• Transactions are nodes

• Edges are signatures

𝑁𝑜𝑑𝑒 ≔

𝑇𝑟𝑎𝑛𝑠𝑎𝑐𝑡𝑖𝑜𝑛

𝐸𝑑𝑔𝑒≔ 𝑆𝑖𝑔 𝑃

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A transaction is a node:

1. Node and edge structure - nodes

𝐼𝑛𝑝𝑢𝑡𝑠 𝑂𝑢𝑡𝑝𝑢𝑡𝑠

𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒

𝑁𝑜𝑑𝑒 =

𝑆𝑖𝑔 𝑃𝑝𝑎𝑟𝑒𝑛𝑡 𝑃𝑛𝑜𝑑𝑒

𝑇𝑥𝐼𝐷𝑝𝑎𝑟𝑒𝑛𝑡

OP_RETURN

Node

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1. Node and edge structure - nodes

A transaction is a node:



𝑁𝑜𝑑𝑒 =

𝑆𝑖𝑔 𝑃𝑠𝑜𝑢𝑟𝑐𝑒 𝑃𝑛𝑜𝑑𝑒

< 𝑁𝑢𝑙𝑙 >

OP_RETURN

“Root” node

Minimum

required

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1. Node and edge structure - edges

A signature creates an edge:


𝑇𝑥𝐼𝐷1

𝑆𝑖𝑔 𝑃0

OP_RETURN

𝑃1

𝑇𝑥𝐼𝐷0


𝑇𝑥𝐼𝐷0

OP_RETURN

𝑃0

Edge

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𝑇𝑥𝐼𝐷1

𝑆𝑖𝑔 𝑃0OP_RETURN

𝑃1

𝑇𝑥𝐼𝐷0


Edges do not have to involve direct spending:


𝑇𝑥𝐼𝐷0

OP_RETURN

𝑃0


𝑇𝑥𝐼𝐷𝑠𝑜𝑢𝑟𝑐𝑒

[Checksig 𝑃0 ]

𝑇𝑥𝐼𝐷𝑠𝑜𝑢𝑟𝑐𝑒 , 0

Metanet edge

Bitcoin spending

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Edges do not have to involve direct spending:


𝑇𝑥𝐼𝐷0

OP_RETURN

𝑃0

[Checksig 𝑃0 ]


𝑇𝑥𝐼𝐷1

𝑇𝑥𝐼𝐷𝑠𝑜𝑢𝑟𝑐𝑒 , 0

𝑆𝑖𝑔 𝑃0

Metanet edge

Bitcoin spending

OP_RETURN

𝑃1

𝑇𝑥𝐼𝐷0

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Each node has an associated unique pair:

• 𝑃𝑛𝑜𝑑𝑒 - the ‘address’ of a node.

• 𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒 - the ‘version’ of a node.

These form a unique node identifier:

𝐼𝐷𝑛𝑜𝑑𝑒 ≔ 𝐻 𝑃𝑛𝑜𝑑𝑒 ∥ 𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒

1. Node and edge structure – node IDs

𝑃𝑛𝑜𝑑𝑒, 𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒

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𝑃𝑛𝑜𝑑𝑒


Simplified notation:

1. Node and edge structure – node IDs



=



OP_RETURN

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A node specifies 𝑰𝑫𝒏𝒐𝒅𝒆 and 𝑰𝑫𝒑𝒂𝒓𝒆𝒏𝒕 :



1. Node and edge structure - node IDs



=



OP_RETURN

𝐼𝐷𝑛𝑜𝑑𝑒 ≔ 𝐻 𝑃𝑛𝑜𝑑𝑒 ∥ 𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒

𝐼𝐷𝑝𝑎𝑟𝑒𝑛𝑡 ≔ 𝐻 𝑃𝑝𝑎𝑟𝑒𝑛𝑡 ∥ 𝑇𝑥𝐼𝐷𝑝𝑎𝑟𝑒𝑛𝑡

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1. Node and edge structure - rules

The rules for the Metanet graph are:

• Nodes are transactions

• Edges are created by signatures

• A node must specify 𝐼𝐷𝑛𝑜𝑑𝑒 and 𝐼𝐷𝑝𝑎𝑟𝑒𝑛𝑡

• A node can have:

▪ 0 or 1 parent (in degree = 0,1)

▪ Arbitrary number of children (out degree = free)

𝑅𝑜𝑜𝑡 𝑛𝑜𝑑𝑒𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷1

𝑃1

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1. Node and edge structure - permissioning

A child of a node can only be created by the owner of 𝑷𝒏𝒐𝒅𝒆:


𝑇𝑥𝐼𝐷𝐴𝑙𝑖𝑐𝑒,2

𝑆𝑖𝑔 𝑃𝐴𝑙𝑖𝑐𝑒

OP_RETURN

𝑃𝐴𝑙𝑖𝑐𝑒,2

𝑇𝑥𝐼𝐷𝐴𝑙𝑖𝑐𝑒



OP_RETURN

𝑃𝐴𝑙𝑖𝑐𝑒

Edge

Bitcoin-valid

Metanet-valid

Metanet-valid

Bitcoin-valid

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A child of a node can only be created by the owner of 𝑷𝒏𝒐𝒅𝒆:


𝑇𝑥𝐼𝐷𝐴𝑙𝑖𝑐𝑒,2

𝑆𝑖𝑔 𝑃𝐵𝑜𝑏

1. Node and edge structure - permissioning

OP_RETURN

𝑃𝐴𝑙𝑖𝑐𝑒,2




OP_RETURN

𝑃𝐴𝑙𝑖𝑐𝑒

Edge

Bitcoin-valid

Metanet-valid

Metanet-invalid

Bitcoin-valid

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Only 𝑷𝟎 can create:𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷2,1

𝑃2,1

𝑇𝑥𝐼𝐷2

𝑃2

𝑇𝑥𝐼𝐷1

𝑃1

𝑇𝑥𝐼𝐷1,1

𝑃1,1

𝑇𝑥𝐼𝐷1,2

𝑃1,2

𝑇𝑥𝐼𝐷2,2

𝑃2,2

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Only 𝑷𝟏 can create:𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷2,1

𝑃2,1

𝑇𝑥𝐼𝐷2

𝑃2

𝑇𝑥𝐼𝐷1

𝑃1

𝑇𝑥𝐼𝐷1,1

𝑃1,1

𝑇𝑥𝐼𝐷1,2

𝑃1,2

𝑇𝑥𝐼𝐷2,2

𝑃2,2

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Only 𝑷𝟐 can create:𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷2,1

𝑃2,1

𝑇𝑥𝐼𝐷2

𝑃2

𝑇𝑥𝐼𝐷1

𝑃1

𝑇𝑥𝐼𝐷1,1

𝑃1,1

𝑇𝑥𝐼𝐷1,2

𝑃1,2

𝑇𝑥𝐼𝐷2,2

𝑃2,2

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𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷2,1

𝑃2,1

𝑇𝑥𝐼𝐷2

𝑃2

𝑇𝑥𝐼𝐷1

𝑃1

𝑇𝑥𝐼𝐷1,1

𝑃1,1

𝑇𝑥𝐼𝐷1,2

𝑃1,2

𝑇𝑥𝐼𝐷2,2

𝑃2,2

𝑰𝑫𝟎 = 𝑯 𝑷𝟎 ∥ 𝑻𝒙𝑰𝑫𝟎

𝑰𝑫𝟐 = 𝑯 𝑷𝟐 ∥ 𝑻𝒙𝑰𝑫𝟐𝑰𝑫𝟏 = 𝑯 𝑷𝟏 ∥ 𝑻𝒙𝑰𝑫𝟏

𝑯 𝑷𝟏,𝟏 ∥ 𝑻𝒙𝑰𝑫𝟏,𝟏 𝑯 𝑷𝟏,𝟐 ∥ 𝑻𝒙𝑰𝑫𝟏,𝟐 𝑯 𝑷𝟐,𝟏 ∥ 𝑻𝒙𝑰𝑫𝟐,𝟏 𝑯 𝑷𝟐,𝟐 ∥ 𝑻𝒙𝑰𝑫𝟐,𝟐

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𝑃0

𝑇𝑥𝐼𝐷0

𝑃1,1

𝑇𝑥𝐼𝐷1,1

𝑃1,2

𝑇𝑥𝐼𝐷1,2

𝑃1

𝑇𝑥𝐼𝐷1

𝑃3

𝑇𝑥𝐼𝐷3

𝑃2

𝑇𝑥𝐼𝐷2

𝑃1,1,1

𝑇𝑥𝐼𝐷1,1,1

𝑃1,2,1


𝑃3,1

𝑇𝑥𝐼𝐷3,1

𝑃3,1,1


𝑃3,1,2


𝑃3,1,3


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The Metanet :

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Content of transactions:

• Metanet flag

• Attributes

• Content data


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𝐼𝑛𝑝𝑢𝑡𝑠


𝑆𝑖𝑔 𝑃𝑝𝑎𝑟𝑒𝑛𝑡𝑃𝑛𝑜𝑑𝑒


𝑂𝑢𝑡𝑝𝑢𝑡𝑠

OP_RETURN

𝑀𝑒𝑡𝑎𝑛𝑒𝑡 𝐹𝑙𝑎𝑔

⋯

⋯

𝐷𝑎𝑡𝑎

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𝑆𝑖𝑔 𝑃𝑝𝑎𝑟𝑒𝑛𝑡


OP_RETURN




⋯

⋯

𝐷𝑎𝑡𝑎

2. Metanet-valid transactions Metanet flag:

• 4-byte protocol flag.

• Indicates Metanet subset of

Bitcoin.

• A global identifier for

protocols.

• Chosen by vote.

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OP_RETURN




⋯

⋯

𝐷𝑎𝑡𝑎

2. Metanet-valid transactions Attributes:

• Metadata related to the

node.

• Implement other protocols

within Metanet.

• E.g. protocol identifiers,

keywords, file types, file

names.

• Application-specific.

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OP_RETURN




⋯

⋯

𝐷𝑎𝑡𝑎

2. Metanet-valid transactions Content data:

• The main data payloads

related to the node.

• E.g. documents, media files,

web-pages, encrypted

messages, social media.

• Non-compulsory – nodes do

not have to include payloads.

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The Metanet is the umbrella protocol:

• Attributes and data can encode any

other protocol.

• The Metanet protocol-specific

elements provide structure.





OP_RETURN




⋯

⋯

𝐷𝑎𝑡𝑎

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2. Metanet-valid transactions - examples

Demonstration of Metanet-valid transactions for:

• Simple data insertion - B://

• Insertion across transactions - B://cat

• Overwriting data - D://

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OP_RETURN




[Protocol ID]

[Data]

[Attributes]

Protocol

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B://𝐼𝑛𝑝𝑢𝑡𝑠




OP_RETURN




[Data]

[Media Type]

[Encoding]

[Filename]

[19Hxiz…ZVdoAut]

B://

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B://𝐼𝑛𝑝𝑢𝑡𝑠




OP_RETURN




[Image Buffer]

image/png

binary

duck.png

[19Hxiz…ZVdoAut]

B://

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𝑇𝑥𝐼𝐷2

𝑆𝑖𝑔 𝑃0


OP_RETURN

𝑃2

𝑇𝑥𝐼𝐷0



𝑇𝑥𝐼𝐷1

𝑆𝑖𝑔 𝑃0


OP_RETURN

𝑃1

𝑇𝑥𝐼𝐷0


B://cat

[Data Part 1]

[Media Type 1]

[Encoding 1]

[Filename 1]

[19Hxiz…ZVdoAut]

B://

[Data Part 2]

[Media Type 2]

[Encoding 2]

[Filename 2]

[19Hxiz…ZVdoAut]

B://

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B://cat𝐼𝑛𝑝𝑢𝑡𝑠

𝑇𝑥𝐼𝐷0



OP_RETURN

𝑃0



[Info]

[MIME type]

[charset]

[name]

[15DHFx…4W6h4Up]

B://cat

[flag]

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B://cat𝐼𝑛𝑝𝑢𝑡𝑠

𝑇𝑥𝐼𝐷0



OP_RETURN

𝑃0



[Info]

[MIME type]

[charset]

[name]

[15DHFx…4W6h4Up]

[flag]

B://catMetanet edges

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D://𝐼𝑛𝑝𝑢𝑡𝑠




OP_RETURN




[key]

[value]

[type]

[sequence]

[19iG3W…TiFesNU]

D://

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B://cat

D://

Protocol locality:

B://

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3. Data insertion

Metanet protocol is compatible with:

• OP_RETURN

• OP_DROP








[Combination protocol]

OP_RETURN

[File data 1] OP_DROP

[File data 2] OP_DROP

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4. Interpreting the graph

The properties of the graph allow:

• Version control

• Domain structure

• Searching

• Integration of key management

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4. Interpreting the graph - versioning

Metanet allows proof-of-work versioning:

• Multiple nodes can share a 𝑃𝑛𝑜𝑑𝑒

• Each has different 𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒

• Distinguish versions by PoW:

▪ Between blocks



𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒′


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4. Interpreting the graph - versioning

Metanet allows proof-of-work versioning:

• Multiple nodes can share a 𝑃𝑛𝑜𝑑𝑒

• Each has different 𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒

• Distinguish versions by PoW:

▪ Between blocks

▪ Within blocks



𝑇𝑥𝐼𝐷𝑛𝑜𝑑𝑒′


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Versioning:

𝑇𝑥𝐼𝐷1

𝑃1

𝑇𝑥𝐼𝐷1,1

𝑃1,1

𝑇𝑥𝐼𝐷1,2

𝑃1,2

𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷2

𝑃2

𝑇𝑥𝐼𝐷2′

𝑃2


𝑃2

𝑻𝒙𝑰𝑫𝟐

𝑻𝒙𝑰𝑫𝟐′

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Versioning:

𝑇𝑥𝐼𝐷1

𝑃1

𝑇𝑥𝐼𝐷1,1

𝑃1,1

𝑇𝑥𝐼𝐷1,2

𝑃1,2

𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷2

𝑃2

𝑻𝒙𝑰𝑫𝟐

𝑻𝒙𝑰𝑫𝟐′


𝑃2

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4. Interpreting the graph - domains

Domain structure is a property:

• Root nodes can be TLDs.

• Non-root can be sub-domains.

• On-chain resources anchored.

𝑇𝑥𝐼𝐷0

𝑃0

𝑷𝟎

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20𝑃0

𝑇𝑥𝐼𝐷0

𝑃1,1

𝑇𝑥𝐼𝐷1,1

𝑃1,2

𝑇𝑥𝐼𝐷1,2

𝑃1

𝑇𝑥𝐼𝐷1

𝑃2

𝑇𝑥𝐼𝐷2

𝑃2,1

𝑇𝑥𝐼𝐷2,1

𝑃2,1,1


𝑃2,1,2


𝑃2,1,3


Domain

𝑷𝟎

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Domains 𝑷𝟏 and 𝑷𝟐

𝑃0

𝑇𝑥𝐼𝐷0

𝑃1,1

𝑇𝑥𝐼𝐷1,1

𝑃1,2

𝑇𝑥𝐼𝐷1,2

𝑃1

𝑇𝑥𝐼𝐷1

𝑃2

𝑇𝑥𝐼𝐷2

𝑃2,1

𝑇𝑥𝐼𝐷2,1

𝑃2,1,1


𝑃2,1,2


𝑃2,1,3


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20𝑃0

𝑇𝑥𝐼𝐷0

𝑃1,1

𝑇𝑥𝐼𝐷1,1

𝑃1,2

𝑇𝑥𝐼𝐷1,2

𝑃1

𝑇𝑥𝐼𝐷1

𝑃2

𝑇𝑥𝐼𝐷2

𝑃2,1

𝑇𝑥𝐼𝐷2,1

𝑃2,1,1


𝑃2,1,2


𝑃2,1,3


𝑷𝟎

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4. Interpreting the graph – locating resources

We define a Metanet-URL (MURL) as:

′mnp:′ +′//domain name′ + ′/path′ + ′/file′

• One MURL corresponds to one transaction:

𝑇𝑥𝐼𝐷1,2

𝑃1,2mnp://bobsblog/sport/tennis

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nChain

20Naming and addressing

𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷2

𝑃2

𝑇𝑥𝐼𝐷1

𝑃1

𝑇𝑥𝐼𝐷1,1

𝑃1,1

𝑇𝑥𝐼𝐷1,2

𝑃1,2

Definition: MURL

mnp://domainname/path/file

The

Metanet

protocol

identifier

Domain

name

mapped to

𝐼𝐷𝑟𝑜𝑜𝑡

Path to

target

node

Name

associated with

target node

• Allow efficient lookup of

content.

• Allow searching by key-

word.

• Human-interpretable method

of traversing the graph.

• Definition: MURL


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𝑇𝑥𝐼𝐷0

𝑃0

𝑇𝑥𝐼𝐷2

𝑃2

𝑇𝑥𝐼𝐷1

𝑃1

𝑇𝑥𝐼𝐷1,1

𝑃1,1

𝑇𝑥𝐼𝐷1,2

𝑃1,2mnp://bobsblog/sport/tennis

“Bob’s blog”

“sport” “finance”

“tennis”“golf”

• Allow efficient lookup of

content.

• Allow searching by key-

word.

• Human-interpretable method

of traversing the graph.

• Definition: MURL


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4. Interpreting the graph – key management

𝑷0

𝑷1 𝑷3𝑷2

𝑷1,1 𝑷1,2 𝑷3,1

𝑷1,1,1 𝑷1,2,1 𝑷3,1,1 𝑷3,1,2 𝑷3,1,3

HD Key Tree Metanet tree

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Use case examples

Building on the Metanet

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UC1: Institutional record storage

Year 1 Year 2

Storage of records:

• Institution key anchored.

• Encrypted by institution.

• Transparently recorded.

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20

UC2: Social media

Profile

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20

UC2: Social media

Feed

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20

Interacting trees:

Pointer

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20

Vote on your preferred flag:

Metanet Flag

META (0x6d657461)

MTNT (0x6d746e74)

METN (0x6d65746e)

MNET (0x6d6e6574)

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The take-away message:

Everybody can start to build structured,

on-chain applications using the Metanet protocol

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• Release of technical summary.

• Metanet blog series.

Announcements

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20

Thank you.

the metanet - nchain · 2020. 9. 17. · planaria bitcom a.n.n.e bit:// map aip preserve sticker...

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