Frequently Asked Questions (FAQs)
CLOCKSS, or Controlled LOCKSS (Lots of Copies Keep Stuff Safe), is a shared dark archive that runs on LOCKSS technology. CLOCKSS’s content is hosted on 12 servers around the world, at leading academic libraries, with robust infrastructure and security.
Research libraries join CLOCKSS to ensure the world's digital content is protected for future generations of researchers. Publishers contribute the content they publish to CLOCKSS to preserve it for the long-term in a secure digital archive without incurring the expense of building their own preservation and storage system. When a publisher's content is triggered, libraries and researchers are not charged for access; instead, the triggered content is made available open access and for free. Join the CLOCKSS growing community.
Digital objects have no meaning on their own. They are not static and reified, and they do not remind us of their value by sitting on a shelf within reach with their titles in view on their spines or on their covers. The threats that put this information at risk also exist out of our sight and could make these digital objects irretrievable. A comprehensive means of preserving, safeguarding, and making accessible digital objects for the future, especially those objects that comprise the record of advances in human knowledge, is an essential foundation for human progress. That is what digital preservation is all about. Digital preservation can never be a solved problem. It is work that does not finish, and it becomes harder over time as formats, software, and hardware fade into memory, and the creators and publishers move on to new challenges.
Preservation requires active management to ensure that content and data is, and remains, healthy. Digitized content, back-up copies, and content in storage can deteriorate over time.
Any library or publisher, worldwide. To be successful we must think beyond CLOCKSS. We must work together. That is why we are committed to equality and diversity and seek to collaborate with partners located all around the world. Our ‘common good’ approach is doing what is in the best interest of the global scholarly community and the knowledge we work to preserve.
Find out more about our current supporting libraries and publishers here.
Research Library Community
Academic Publisher Community
CLOCKSS leverages existing infrastructure
CLOCKSS Archive nodes — the host libraries for the archived content - are housed at long-established institutions, supporting the library's role as a "custodian of culture." These 12 institutions are located in geographically, politically, and geologically disparate locations in North America, Europe, and Asia-Pacific.
CLOCKSS runs on proven digital preservation technology
Underlying CLOCKSS is the LOCKSS technology developed at Stanford University, which has been safely and securely preserving web-published content since 1999. Since then it has evolved with web advances to preserve new content types.
Underlying CLOCKSS is the LOCKSS technology, which has been safely and securely preserving web-published content since 1999. Since then, it has evolved with web advances to preserve new content types.
A trusted archive is one that has demonstrated its ability to preserve content in the long term. This can be demonstrated through means such as:
• Relevant certification including peer review by library experts (e.g. CRL TRAC audit, ISO:16363)
• Demonstrated mandate and funding
• A demonstrated track record of preserving academic content
• Clearly documented agreements, workflows, and processes to ensure long-term access to the repository’s contents
• A succession plan so it is clear what happens to content if the archive goes under
Yes. We hold the highest certification score ever awarded by the TRAC audit operated by the Center for Research Libraries. We have a mandate and sustainable business model, a demonstrated track record of preserving academic content, open and transparent documentation, and a succession plan should anything happen to us.
The CLOCKSS Board of Directors includes an equal number of seats for libraries and for publishers, thereby balancing their influence on CLOCKSS policies, priorities, and the decisions that will impact them the most.
CLOCKSS provides participants with the opportunity to be more deeply involved in industry-wide efforts that are shaping the future, which helps to keep the community’s best interests at the forefront.
CLOCKSS uses the award-winning LOCKSS system, which was invented specifically for the long-term digital preservation of scholarly content. CLOCKSS holds the highest score ever awarded from the TRAC audit conducted by the Center for Research Libraries and is the only Trusted Digital Repository to receive the highest score for technology.
Triggered content is made freely available open access to everyone.
CLOCKSS is a tax-exempt, 501(c)3, not-for-profit charitable organization. Annual fees are set by the Board of Directors and are based on publishing revenues for publishers and materials budgets for libraries. Publishers also pay a transactional fee based on how much content they preserve in the Archive.
The CLOCKSS Board of Directors is committed to these values, to ensure the organization’s sustainability:
• Because money spent on digital archiving competes with other needs, CLOCKSS is committed to minimizing publishers’ fees so that publishers will not pass along additional costs to libraries. CLOCKSS also aims to minimize libraries’ fees, so that they have more money to spend on content from publishers.
• All triggered content is made freely available open access. CLOCKSS will not create additional access barriers.
Because CLOCKSS is a 501(c)3 not-for-profit organization, all contributions to CLOCKSS are tax deductible in the US.
For ever additional preservation service you add the risk to digital content is reduced by 50%. Good practice is to preserve content in at least three digital archives.
Because CLOCKSS runs on proven, low-cost, open-source LOCKSS software, the costs for participation are affordable for libraries and publishers. See our current fees here
CLOCKSS is a not-for-profit joint venture developed by libraries and publishers who guide its management and future. Unlike other archiving solutions, CLOCKSS answers to its community, not to a parent company. Find out more about the CLOCKSS community here
Ideally, important content should be preserved with at least 3 trusted archives. 3 is the magic number when it comes to digital preservation services – each additional service roughly halves the chance of loss.
• The more copies the safer. Presumably, each of the three services maintains more than one copy, so the number of copies is likely several times three.
• The less correlated the copies the safer. Presumably, each of the three services is running different software, under a different administration, and each is geographically distant from the others. So although the correlations among the copies at each service will be quite high, the correlation among the different services will be low.
• The more reliable each copy the safer. Each of the three services is striving to be reliable, so the level of reliability of each of them will be relatively high.
• The faster failures are detected and repaired the safer. Presumably, each of the three services is running fixity checks on a different, uncorrelated schedule.
Trigger events happen when content is permanently removed, for example because:
Publisher No Longer in Business
The publisher is no longer in business or is no longer in the business of publishing content or providing access to previously published content, and there are no successor interests or reversions or transfers of rights.
Title No Longer Offered
The publisher is no longer providing access to the content and there are no successor interests or reversion or transfer of rights.
Back Issues No Longer Available
The publisher has stopped offering or providing access to some or all of the back issues of the content and there are no successor interests or reversion or transfer of rights.
While still publishing content, the publisher is not able to provide access to the content electronically due to technical or similar catastrophic and permanent failure.
Everyone. The materials are made available to everyone for free and open access.
Take a look at these examples (a, b, c), which are accessible from Triggered Content on the CLOCKSS website.
Why should libraries contribute towards CLOCKSS, when triggered content will be freely available to everyone?
CLOCKSS exists to preserve the hard work and knowledge of scholars. To deliver on this mission we work to make sure that archiving remains in the hands of the community -- this is a mission for today and in perpetuity and is the reason that the Board of Director is comprised equally of libraries and publishers. By contributing to CLOCKSS, your organization becomes part of that community of libraries and publishers and you gain a direct voice in archiving decisions.
The active support of libraries strengthens our influence with publishers, enabling us to persuade more to entrust the content they publish to the archive. We also work with library publishers to ensure these important publications become part of the international scholarly record preserved in CLOCKSS.
CLOCKSS complements and supports your own digital preservation strategy. It is more cost effective and efficient to collaborate to preserve published digital books and journals rather than each institution duplicating this effort. That frees you to focus on the unique content that you hold and make available.
CLOCKSS also saves your library money by reducing the risk that you will be asked to pay for access to orphaned content. Publishers who participate in CLOCKSS agree that we can make triggered content available open access, and grant us the rights to do this in perpetuity.
Library supports enables us to subsidize preservation costs for the long-tail of new and smaller publishers whose content is most at-risk. For example, this includes diamond open access titles via the JASPER Project.
No. LOCKSS stands for Lots of Copies Keeps Stuff Safe. The LOCKSS name has come over time to refer to at least 3 different things:
1. it is the name of preservation software developed by Stanford university. The LOCKSS technology is “fault tolerant” and safeguards against the long-term, well-documented causes of digital loss: human error, computer attacks, economic and organizational failure.
2. The LOCKSS technology preserves all formats (video, sound, pictures, text, etc.) and genres of content (e-journals, e-books, conference proceedings, etc.).
3. it is in the name of the Global LOCKSS network which provides distributed preservation and local post-cancellation and perpetual access for subscription electronic journals and books, as well as a mechanism for building local collections of web-based scholarly open access publications.
4. a community of varied distributed preservation services all operating on LOCKSS software. These preservation services are: the Alabama Digital Preservation Network (ADPN), Cariniana, CLOCKSS, MetaArchive, the Michigan Digital Preservation Network (MDPN), SAFE PLN, US Docs PLN, CGI PLN, and PKP PLN.
CLOCKSS is a global archive that preserves content on behalf of all libraries and scholars worldwide. CLOCKSS does so in 12 strategically chosen academic libraries across the globe to optimize the content’s safety against political and environmental threats. Located in Asia-Pacific, Europe, and North America, they each have a complete copy of the archive. They perform the preservation service on behalf of libraries and users everywhere; other libraries do not need to host the published scholarly literature for preservation purposes themselves. Many libraries support CLOCKSS through financial contributions and by participating in Archive governance; they do not need to host any technology locally. CLOCKSS is considered a “controlled LOCKSS" archive because of the unique role of the 12 nodes.