◆ Semantic Web Catalogue

Problem thread

Names that outlive their hosts

How can a name keep working after the server, the company or the domain behind it is gone?

issue
identification
also sustainability
status
open
steps
9, 1994–2022
threads
all problem threads

A web address names a location, so it breaks when the content moves or the host disappears. Three kinds of answer have been tried: redirection services run by an institution (PURL, DOI, w3id.org), archives that keep copies (the Wayback Machine), and names computed from the content itself (IPFS) or controlled by their subject (DIDs). Each depends on someone continuing to do the work, and a 2014 study found that one in five scholarly articles already cites web pages that have gone or changed.

Lineage

  1. Jun 1994
    precedent concept ★ seminal
    URI

    RFC 1630 defines the syntax the Web uses to encode the names and addresses of objects on the Internet, one scheme for both. [src]

  2. 1995
    proposes standard ★ seminal
    PURL

    OCLC's resolver: a URL that points at a redirect service rather than at the resource, so the target can move without breaking the name. [src1][src2]

  3. 1998
    poses writing ★ seminal
    Cool URIs don't change

    Argues that a URI, once published, should keep working indefinitely: breaking links is a choice made by poor design, not an accident of technology. [src]

  4. 2000
    proposes standard ★ seminal
    DOI

    An identifier for the object itself, physical, digital or abstract. The DOI system redirects to wherever the object is now, and its metadata can change without changing the DOI. [src]

  5. 25 Oct 2001
    workaround project ★ seminal
    Wayback Machine

    Keeps copies instead of keeping names working: an archive of crawled pages back to 1996, where a dead link can often still be read. [src]

  6. 2013
    proposes project
    w3id.org

    A community-run redirect service: anyone can claim a path by pull request, and a consortium of organisations has pledged to keep it running. [src1][src2]

  7. 14 Jul 2014
    proposes writing ★ seminal
    IPFS – Content Addressed, Versioned, P2P File System

    Names data by its content through a self-certifying namespace, so any node holding a copy can serve it and there is no single point of failure. [src]

  8. 26 Dec 2014
    measures writing ★ seminal
    Scholarly Context Not Found: One in Five Articles Suffers from Reference Rot

    Across millions of links in scholarly articles, about one in five articles cites web resources that have since vanished or changed. [src]

  9. 19 Jul 2022
    proposes standard ★ seminal
    Decentralized Identifiers

    Identifiers that their subject can create and control without a central registry; DID 1.0 became a W3C Recommendation in July 2022. [src]

Recent signals

Dated events that show the problem moving, newest last.

  1. 5 Mar 2026

    DID 1.1 becomes a W3C Candidate Recommendation. Decentralized Identifiers[src]

  2. 6 Aug 2026

    DID Resolution reaches Candidate Recommendation, defining how a DID is turned into its DID document. Decentralized Identifiers[src]

Open now

Under each question, the answers people have put forward or built. The catalogue gives no odds on them.

  • Who keeps a redirect service running when the institution that started it loses interest? [src1][src2]
    PURL moved from OCLC to the Internet Archive after twenty years; w3id.org relies on a pledge from a consortium of organisations.
    • A volunteer community group runs it. w3id.org
      w3id.org is kept by the W3C Permanent Identifier Community Group, with redirects managed in a public repository.[src]
    • A large archive takes it over. PURL
      The PURL service moved from OCLC to the Internet Archive in 2016.[src]
  • How should DIDs be resolved, so that different systems agree on what a DID points to? [src]
    The W3C DID Working Group lists DID resolution and DID URL dereferencing as the route to interoperability it is working on.
    • A W3C standard fixes the resolution algorithm. Decentralized Identifiers
      DID Resolution defines inputs, outputs and metadata, and needs two independent interoperable implementations of every feature to advance.[src]

Forces

Pressures that push this problem one way or another, as their sources argue them. All forces

  • Distrust of platform owners

    Names tied to a company's domain or server last only as long as the company; that risk motivates persistent identifiers and DIDs.[src]

Decision points

Dated moments when a decision or a deadline can change the outcome.

  1. 31 Jan 2027
    DID Working Group charter ends charter

    The W3C group behind DID 1.1 and DID Resolution is chartered until this date.[src]

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