Digital Preservation for Journals: Complete Guide to LOCKSS, PKP PN, Portico & More

Digital preservation ensures that scholarly content remains accessible long after publication—even if a journal ceases publication, a publisher goes out of business, or hosting infrastructure fails. For academic journals, having a documented archiving strategy is not just best practice—it's increasingly required by indexing services like DOAJ, Scopus, and funders. This comprehensive guide explains the major preservation options available to journals, with particular focus on solutions accessible to OJS-based publications.

Why Digital Preservation Matters

The scholarly record is at risk. A 2024 study published in the Journal of Librarianship and Scholarly Communication found alarming statistics:

• 76% of online resources tracked by ISSN are not preserved in any Keepers archive
• 33% of Crossref members do not preserve their content in any recognized archive
• Only 1% of Crossref members preserve content at the "Gold" level (75%+ content in 3+ archives)
• Over 170 open access journals have already vanished from their publishers' websites in the past two decades

Without preservation, scholarly work can disappear permanently when:

• Publishers cease operations
• Hosting platforms fail or are discontinued
• Domain names expire and are acquired by unrelated parties
• Content is accidentally deleted or corrupted
• Natural disasters or cyberattacks destroy infrastructure

Understanding "Dark Archives" vs. "Light Archives"

Before exploring specific services, understand two key concepts:

Dark Archives

Content is preserved but not publicly accessible until a "trigger event" occurs (e.g., the journal ceases publication, publisher goes out of business, or content is no longer available from any source). Examples: CLOCKSS, PKP PN, Portico.

Light Archives

Content is publicly accessible regardless of the original source's status. Examples: Internet Archive, institutional repositories.

Most formal preservation services operate as dark archives, releasing content only when necessary to preserve access to the scholarly record.

Major Preservation Services

PKP Preservation Network (PKP PN)

Best for: OJS journals not enrolled in other preservation services

Cost: Free

Type: Dark archive

What It Is

The PKP Preservation Network is a free service developed by the Public Knowledge Project specifically for OJS journals. Built on LOCKSS technology, it provides decentralized, distributed preservation with multiple copies across different nodes.

Requirements

• OJS version 3.1.2 or newer (current version: 3.5.x)
• At least one published article
• Valid ISSN registered
• CURL and ZipArchive PHP extensions enabled
• Scheduled tasks properly configured

How to Enable

1. Log into OJS as Site Administrator
2. Navigate to Settings → Website → Plugins
3. Find PKP|PN in the Plugin Gallery and install it
4. Enable the plugin
5. Open plugin settings and review Terms of Use
6. Accept all terms and save

After enabling: Your journal's content (retrospective and new) is automatically deposited. No further action required unless terms are updated.

Current Status

As of 2024, the PKP PN hosts content from over 1,700 journals across 7 preservation nodes. Content is only made accessible after a "trigger event" when the journal becomes unavailable from its original source.

LOCKSS (Lots of Copies Keep Stuff Safe)

Best for: Journals seeking distributed preservation through library networks

Cost: Free for publishers (no participation fee)

Type: Distributed archive (access depends on trigger conditions)

What It Is

LOCKSS is open-source software developed by Stanford Libraries since 1999. It enables libraries to collect, preserve, and provide access to published content. Libraries run "LOCKSS boxes" that crawl permitted content and maintain copies, voting on cryptographic hashes to detect and repair corruption.

Global LOCKSS Network (GLN)

The GLN is the primary network providing:

• Post-cancellation access: Libraries access preserved content after subscription ends
• Post-disappearance access: Content available if publisher's site disappears
• Failover access: Backup when publisher's site is temporarily unavailable

How It Works for Publishers

1. Contact the LOCKSS Program expressing interest
2. Provide: publisher name, titles, ISSNs, first issue dates, where indexed, platform
3. If accepted, create a LOCKSS Publisher Manifest on your journal site
4. LOCKSS libraries crawl and preserve your content

OJS Integration

OJS has built-in LOCKSS support:

1. Go to Settings → Distribution → Archiving
2. Enable LOCKSS checkbox

Important: Enabling LOCKSS in OJS displays your intent and creates the Publisher Manifest, but does not automatically enroll your journal. You must also contact LOCKSS for formal inclusion in the Global LOCKSS Network.

CLOCKSS (Controlled LOCKSS)

Best for: Established publishers seeking comprehensive dark archive preservation

Cost: Fees vary based on content volume (contact for pricing)

Type: Dark archive

What It Is

CLOCKSS is a non-profit 501(c)(3) partnership between research libraries and publishers, using LOCKSS technology. Unlike the GLN, CLOCKSS operates as a true dark archive—content is only released when triggered, and triggered content receives Creative Commons open access licenses.

Key Features

• 12 archive nodes at leading research libraries worldwide
• Governance: Board includes publishers and library representatives
• Preserves journals, books, supplementary materials, data, software, videos, web archives
• Triggered content becomes open access under Creative Commons license
• Center for Research Libraries TRAC certified (5/5 rating)

How to Participate

1. Contact CLOCKSS to discuss inclusion
2. Negotiate participation agreement and fees
3. Arrange content delivery (various ingest methods available)
4. Content is preserved across distributed nodes

OJS Integration

Similar to LOCKSS, enabling CLOCKSS in OJS (Settings → Distribution → Archiving) displays your archiving affiliation but does not automatically enroll you. A formal agreement with CLOCKSS is required.

Portico

Best for: Publishers seeking established, trusted third-party preservation

Cost: Participation fees (community-supported model)

Type: Dark archive

What It Is

Portico is operated by ITHAKA (also behind JSTOR) and has been preserving e-journals since 2005. It's one of the world's largest community-supported digital preservation archives, with over 1,000 publishers and 1,000 libraries participating.

Key Features

• Comprehensive preservation: Journals, e-books, digitized collections
• Format migration: Content converted to archival formats, migrated as needed
• Three geographic locations: Redundant storage across regions
• CRL certified: First digital preservation service to receive Center for Research Libraries certification
• OAIS compliant: Follows Open Archival Information System reference model

Trigger Events

Portico releases content when:

• Publisher ceases operations
• Publisher stops publishing a title (not picked up elsewhere)
• Back issues removed from publisher's offering
• Catastrophic platform failure for sustained period

How to Participate

1. Contact Portico to discuss participation
2. Negotiate licensing and participation agreement
3. Arrange content delivery in required formats
4. Content ingested, validated, and preserved

Internet Archive / Wayback Machine

Best for: Supplementary preservation and public accessibility

Cost: Free (basic), Archive-It subscription for managed service

Type: Light archive (publicly accessible)

What It Is

The Internet Archive is a non-profit digital library preserving over 1 trillion web pages. The Wayback Machine automatically crawls and archives public websites, making historical snapshots accessible.

Key Features

• Internet Archive Scholar: Search index of 35+ million research articles
• Automatic crawling: Public web content collected continuously
• Manual capture: Use "Save Page Now" to capture specific pages
• Archive-It: Subscription service for managed, scheduled archiving
• Publicly accessible: Anyone can access archived content

Considerations

• Not a formal preservation service—content capture is best-effort
• robots.txt restrictions may prevent archiving
• Archived pages may have errors or missing elements
• Does not replace formal preservation services like CLOCKSS or Portico

Best Use

Internet Archive is valuable as a supplementary measure and for public accessibility, but journals should not rely on it as their sole preservation strategy. Use it alongside formal services.

Comparison of Preservation Services

Regional and Specialized Networks

Additional preservation networks serve specific regions or communities:

• Cariniana (Brazil): Preserves Brazilian scientific publications on OJS
• WestVault (Canada): Preserves Western Canadian open access materials via COPPUL
• SciELO: Latin American scientific publishing platform with built-in preservation
• KB e-Depot (Netherlands): National Library of the Netherlands digital archive, open to international publishers
• British Library Legal Deposit: UK publications

What Indexing Services Require

Major indexing services increasingly require documented preservation strategies:

DOAJ

Asks whether journals have a digital archiving policy and which services they use (LOCKSS, CLOCKSS, Portico, PKP PN, PMC, national libraries, or others).

Scopus

Evaluates online availability and content preservation as part of the assessment criteria.

Web of Science

Considers preservation arrangements as part of publishing best practices evaluation.

Funders

Many research funders require that publications be preserved in recognized archives to ensure long-term accessibility of funded research.

Implementing a Preservation Strategy

Step 1: Enable PKP PN (OJS Journals)

If you use OJS and are not enrolled in CLOCKSS or Portico, enable PKP PN immediately. It's free, automatic, and takes minutes.

Step 2: Document Your Policy

Create a preservation/archiving policy page on your journal website stating:

• Which preservation services you use
• How content will remain accessible if the journal ceases publication
• Author rights regarding self-archiving

Example statement:

"This journal utilizes the PKP Preservation Network (PKP PN) to ensure long-term digital preservation of its published content. In the event the journal ceases publication, archived content will be made accessible through the preservation network. Additionally, this journal's content is archived by the Internet Archive."

Step 3: Consider Multiple Services

For maximum protection, use multiple preservation services. The "Gold standard" is content preserved in 3+ archives. Options:

• PKP PN + Internet Archive (free combination)
• PKP PN + LOCKSS GLN (free combination for accepted publishers)
• CLOCKSS + Portico (paid comprehensive coverage)

Step 4: Verify Preservation Status

Check that your preservation is working:

• PKP PN: Plugin shows deposit status in OJS dashboard
• Keepers Registry: keepers.issn.org tracks which journals are preserved where
• Internet Archive: Search your journal URL in the Wayback Machine

Digital Preservation Checklist

Common Mistakes to Avoid

Checking OJS Boxes Without Enrollment

Enabling LOCKSS or CLOCKSS in OJS settings does not automatically enroll your journal in those services. It creates the Publisher Manifest and displays your intent, but you must contact the services separately for actual preservation.

Confusing Journal Archives with Preservation

Your journal's "Archives" page (back issues) is not digital preservation. If your hosting fails, those archives disappear. True preservation requires third-party services maintaining independent copies.

Relying Solely on Internet Archive

While valuable, the Wayback Machine is not a formal preservation commitment. Pages may not be captured, or captures may be incomplete. Use it as supplementary, not primary, preservation.

Not Verifying Deposits

Enable preservation services and then verify they're actually working. Check PKP PN plugin status, search Keepers Registry, confirm with service providers.

How Altechmind Can Help

We configure complete preservation strategies for OJS journals:

• PKP PN Setup: Plugin installation, configuration, and verification
• Scheduled Tasks: Cron job configuration for automated deposits
• LOCKSS Manifest: Proper Publisher Manifest configuration
• Policy Documentation: Archiving policy page creation
• Troubleshooting: Resolving deposit failures and plugin issues
• Verification: Confirming preservation status in Keepers Registry