Decentralized Resource Identifier

Full Name or Meme

A Decentralized Resource Identifier is variant of a Digital object identifier (DOI) that always points to a single object that can always be resolved and recovered.

Context

• Idea articulated by Robert Mitwicki of Dativa at the Semantics Working Group of Hyperledger INDY on 2019-04-16.
• This concept was filtered through the needs of the US Trustworthy Healthcare Ecosystem of the Kantara FIRE working group requirements for a medical records locator.

Problems

• Nothing lasts forever.
• It is important to recover documents in an unchanged format, perhaps many years after the document is created.
• The only commonly agreed type of guarantee that a document has not changed is a hash of the content, but even that requires that we know the hashing algorithm.
• The proposal that a hash of the document be placed on a blockchain makes the assumption that the blockchain will itself survive all the turmoil that is certain in the coming years. Not a good bet.

Solutions

• Build an identifier that will always refer to the document based on its content, rather than the location where it is stored at any point in time.
• Assure some method that the validity of the document can be verified over time.
• Create a naming scheme that will ensure that whoever acquires the identifier and determine how to find the doc and verify its integrity.

Based on Trusted Federations

• Ensure that you can accept the trust provided by the federation.
• Allow the trusted federation to verity the provenance and validity of the document received.

Based on Anarchy

• Ensure that you cannot be located or you will probably wind up regretting your involvement.
• Be prepared for the result that the base system has ceased to function.
• There will be no recourse for failure of the system to provide the document or the integrity of it.

Universals

Note that for a full compatible system where most scalable systems sill use the DNS the "did:" must reserve the top-level domain (tld) to avoid collisions.

doi:some sort of determination of the method used.
iat:some sort of integrity value.

Which would be written as:

doi:{doc description};iat:{integrity statement}

Or for places where the syntax is completely clear:

{doc description};{integrity statement}

US Healthcare Example

This example is taken from draft one of the Distributed Identity Assurance specification, which is sure to experience change before it is finalized.

doi:{name of source of the medical record in reverse dns format}.{record number};iat:{date of check point of the current version of the doc}

Other possibilities

dri:{type}:id;iat:{hash of document}
did:{type}:id;iat:{date}

References

Other Material

• ODCA (Open Data Center Alliance)

  The Open Data Center Alliance (ODCA) is an independent information technology (IT) consortium whose goal is to develop a unified vision of cloud requirements.

• Content centric networking

  In contrast to IP-based, host-oriented, Internet architecture, content centric networking (CCN) emphasizes content by making it directly addressable and routable. Endpoints communicate based on named data instead of IP addresses. CCN is characterized by the basic exchange of content request messages (called "Interests") and content return messages (called "Content Objects"). It is considered an information-centric networking (ICN) architecture.

• IPLD

  IPLD is the data model of the content-addressable web. It allows us to treat all hash-linked data structures as subsets of a unified information space, unifying all data models that link data with hashes as instances of IPLD.

• Magnet URI scheme

  magnet is a URI scheme that defines the format of magnet links, a de facto standard for identifying files (URN) by their content, via cryptographic hash value rather than by their location. Although magnet links can be used in a number of contexts, they are particularly useful in peer-to-peer file sharing networks because they allow resources to be referred to without the need for a continuously available host, and can be generated by anyone who already has the file, without the need for a central authority to issue them. This makes them popular for use as "guaranteed" search terms within the file sharing community where anyone can distribute a magnet link to ensure that the resource retrieved by that link is the one intended, regardless of how it is retrieved.