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Electronic Mail List Preservation Takes Off: The H-Net Archive. Lisa M. Schmidt lisa.schmidt@matrix.msu.edu http://www.h-net.org/archive/ MATRIX: The Center for Humane Arts, Letters & Social Sciences Online Michigan State University May 1, 2009. Preserving the H-Net E-Mail Lists.
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Electronic Mail List Preservation Takes Off: The H-Net Archive Lisa M. Schmidt lisa.schmidt@matrix.msu.edu http://www.h-net.org/archive/ MATRIX: The Center for Humane Arts, Letters & Social Sciences Online Michigan State University May 1, 2009
Preserving the H-Net E-Mail Lists H-Net Background Original “Preservation” Practices Use of the Trustworthy Repositories Audit & Certification: Criteria and Checklist (TRAC) Preservation Improvement Plan
H-Net: Humanities and Social Sciences Online International consortium of scholars and teachers Oldest collection of born-digital and content-moderated arts, humanities, and social science material on the Internet Valuable scholarly resource More than 180 networks, or e-mail lists More than 230 “private” lists More than 1 million e-mail messages Hosted by MATRIX
MATRIX Digital humanities research center Devoted to the application of new technologies in humanities and social science teaching and research Uses Internet technologies to improve education and increase the flow of information
NHPRC Grant Conduct assessment of existing H-Net preservation policies and practices Apply OCLC/CRL TRAC checklist Develop and implement an improved long-term preservation plan Useful to those managing large collections of electronic records Research semantic clustering search techniques
How H-Net Works:Backup & Security 3 TB of data, including H-Net Server rack kept in climate controlled, physically secured room Daily incremental backups, weekly full Monthly full, “permanent” tape backups
How H-Net Works H-Net runs on LISTSERV software Submission policies Users must be list subscribers to post Messages written in plain text No attachments allowed on public lists
How H-Net Works:An Archival Perspective Appraisal/Acquisition/Accession All approved messages permanently archived Editors approve and post messages Messages post from a few seconds up to several days after approval
How H-Net Works:An Archival Perspective Message Posting Process
How H-Net Works:An Archival Perspective Arrangement Messages kept in flat text files called “notebooks” Single notebook includes messages posted during seven-day time period, concatenated in original order
How H-Net Works:An Archival Perspective Arrangement Notebooks appear to be arranged in original order within each list directory
How H-Net Works:An Archival Perspective Description Most descriptive metadata for messages automatically generated on creation/posting “Author’s Subject” inserted by creator
How H-Net Works:An Archival Perspective Notebook File Naming • Notebook description contained in filename - Ex. “h-africa.log0802a”
How H-Net Works:Message Retrieval BRS Database Newest notebook messages parsed and copied every 24 hours MD5 hashes created for each message Available for full-text search MySQL Database Cache Key metadata extracted, MD5 hashes created, written to database cache Enables more efficient browsing
How H-Net Works:Message Retrieval Message Metadata Stored in MySQL Database
How H-Net Works:Message Retrieval http://h-net.msu.edu/cgi-bin/logbrowse.pl?trx=vx&list=H-Albion&month=0808&week=b&msg=w8utW6nKNO1FuY19vSK2mo&user=&pw=
How H-Net Works Message Ingest, Storage, and Retrieval Processes
Original “Preservation” Practices Backup, but only local—and no true archiving No normalization or migration strategy Message/notebook content: No need Created and stored in plain text formats XML encoding only required with proprietary e-mail formats Needed for attachments on private lists
Original “Preservation” Practices Authenticity Informal check by author and/or editor on posting Broken URL on message retrieval attempt Cached metadata as PDI Reference, Content, Provenance Information MD5 hashes for message discovery, not fixity No Fixity Information for notebook files
Trustworthy Repositories Audit & Certification: Criteria and Checklist (TRAC) TRAC 1.0 published in February 2007 For certification by third party or self assessment Three sections A. Organizational Infrastructure B. Digital Object Management C. Technologies, Technical Infrastructure, & Security 84 audit criteria
Trustworthy Repositories Audit & Certification: Criteria and Checklist (TRAC) Compare core audit criteria to local capabilities—“Gap Analysis,” illuminating areas requiring improvement Formulate strategies to narrow the gap and improve trustworthiness of repository
Trustworthy Repositories Audit & Certification: Criteria and Checklist (TRAC) Example 1: Repository has formal succession plan H-Net: No succession plan in place Narrow the gap: Identify, negotiate with, and make preliminary plans with potential successor; document intent, describing what’s needed in successor
Trustworthy Repositories Audit & Certification: Criteria and Checklist (TRAC) Example 2: Repository functions on well-supported operating systems and other core infrastructural software H-Net: Servers run on Debian distribution of Linux No gap!
Trustworthy Repositories Audit & Certification: Criteria and Checklist (TRAC)
The TRAC Experience Thorough yet flexible, leaving room for interpretation, lots of options for supporting documentation/evidence Good snapshot of current state of repository Clarifies what’s needed to narrow the gap Great internal audit tool Useful for certification of a trusted digital repository
Preservation Improvement Plan:Backup & Archival Storage Backup Long-term (“permanent”) backup tape sets stored offsite, put on 3-year retention schedule Reciprocal backup storage arrangement with ICPSR Archival Storage Annual copying to tape of H-Net data, databases,scripts Media refreshment every 5 years Future: Copy to alternative storage repository Future: Participation in distributed archival storage system
Preservation Improvement Plan:Authenticity Fixity: Individual Messages (SIPs/AIPs) Shorten time window for generation of hashes Create database of SHA-256 hashes for fixity checks Validate message hashes on notebook completion Fixity: Notebook Files (AICs) Create SHA-256 message digests on completion of notebooks Calculate SHA-256 message digests for existing notebooks Create database of SHA-256 message digests for fixity checks Validate notebook hashes on weekly basis
Preservation Improvement Plan:Other Technical Improvements Attachments Found with < 0.01% of H-Net messages MS Office, PDF, image files Provide constructed URLs, as with public lists Provide download links No file normalization or migration plan Most files should open in viewers, later versions of applications Will help users if problems arise Preservation of Links to Original Content Redirect URLs within messages to archived websites
Preservation Improvement Plan:Narrowing the Gap Technical improvements Digital preservation policies Lather, rinse, repeat: New TRAC assessment
Conclusions Relevant to e-mail preservation discussion Applicable to preservation of LISTSERV-based and other e-mail lists Testbed for other preservation tools and systems Useful foundation for digital preservation planning at Michigan State
References H-Net Archives Project, http://www.h-net.org/archive/ H-Net: Humanities and Social Sciences Online, http://www.h-net.org MATRIX: The Center for Humane Arts, Letters, and Social Sciences Online, http://www.matrix.msu.edu OAIS Reference Model, http://public.ccsds.org/publications/archive/650x0b1.pdf Trusted Digital Repositories: Attributes and Responsibilities, http://www.oclc.org/programs/ourwork/past/trustedrep/repositories.pdf Trustworthy Repositories Audit & Certification: Criteria and Checklist, http://www.crl.edu/PDF/trac.pdf