Robbi Verte, Gesture of hand holding a flash disk, http://www.123rf.com/Pietro Izzo, Open hand, http://www.flickr.com/photos/pietroizzo/482812880
Luxmart, Working together team puzzle concept, http://commons.wikimedia.org/wiki/File:Working_Together_Teamwork_Puzzle_Concept.jpg
Jason DeRusha, Crying baby shot, http://www.flickr.com/photos/derusha/1465953800Izumi Mitatami, The hamburger, http://www.flickr.com/photos/marvin_izumi/3881467402Sean Dreilinger, Big hamburger, little kid, http://www.flickr.com/photos/seandreilinger/3002176844
Guardian, Five reasons why waiters don’t write down your order, http://www.guardian.co.uk/lifeandstyle/2011/aug/14/waiters-dont-write-orders-down
NCinDC, Life is one big balancing act, http://www.flickr.com/photos/ncindc/3229050640Energy Press,PWC: Το δάνειο στο ΛΑΓΗΕ δεν αρκεί για να μην καταρρεύσει η αγορά, http://www.energypress.gr/news/lianikh-reymatos/PWC:-To-daneio-sto-LAGHE-den-arkei-gia-na-mhn-katarreysei-h-agora
Duncan Hall, Attention aux PickPockets, http://www.flickr.com/photos/dullhunk/4575707721Enrique Martinez Bermejo, Community-manager, http://www.flickr.com/photos/kikemb/5428414543
Transcript of "Design Principles for Digital Preservation Systems"
Design Principles forDigital Preservation SystemsStephen AbramsUniversity of California Curation CenterCalifornia Digital Librarywww.cdlib.org/uc3SystemsSystems?
Design Principles forDigital Preservation SystemsStephen AbramsUniversity of California Curation CenterCalifornia Digital Librarywww.cdlib.org/uc3Programs
WashingtonMay 22-24, 2013What’s the problem we’re trying to solve? Connecting people with digital content in meaningful waysacross barriers of space and time Preservation is the end, systems are just the meansRobbi Verte, Gesture of hand holding a flash disk, www.123rf.com/Pietro Izzo, Open hand, www.flickr.com/photos/pietroizzo/482812880
WashingtonMay 22-24, 2013Think outside the (system) box Worry about designing your overall preservation programbefore considering the systems that will implement parts of itLuxmart, Working together team puzzle concept,http://commons.wikimedia.org/wiki/File:Working_Together_Teamwork_Puzzle_Concept.jpg« Integration »
WashingtonMay 22-24, 2013Think outside the (system) box Worry about designing your overall preservation programbefore considering the systems that will implement parts of it A preservation program should provide effective control overmanaged content in several key areas Technical control Managing bits, descriptions of bits, relationships between bits, etc. Analysis, planning, monitoring, intervention, etc. Intellectual (or curatorial) control Creation, selection/acquisition, arrangement, cataloging, etc.Cf. Kenney & McGovern (2003), “Five organizational stages of digital preservation,” Digital Libraries: A Visionfor the 21st Century (Ann Arbor: MPublishing,), hdl:2027/spo.bbv9812.0001.001« Integration »
WashingtonMay 22-24, 2013Good design is good design Any principles for preservation system design should beinformed by general principles for system design andengineering design Beginning with a clearly defined need Leading to a creative design in response to the need Resulting in a system fully meeting the needCf. Royal Academy of Engineering (1999), Principles of Engineering Designwww.raeng.org.uk/education/vps/principles/pdf/armstrong_keynote.pdfJason DeRusha, Crying baby shot, www.flickr.com/photos/derusha/1465953800Izumi Mitatami, The hamburger, www.flickr.com/photos/marvin_izumi/3881467402Sean Dreilinger, Big hamburger, little kid, www.flickr.com/photos/seandreilinger/3002176844
WashingtonMay 22-24, 2013Design principles for preservation systems Integration Least surprise Definition Elegance Generality Community Parsimony Modularity Granularity Orthogonality Emergence Redundancy Evolution TransienceYes, some of these may sound, or evenbe, somewhat inconsistent orcontradictory
WashingtonMay 22-24, 2013Know what you (really) need What you need, not just what you want Tie requirements to specific use cases Actual, expected, anticipated, or probable Hypothetical? Acceptance criteria Did you get what you asked for?« Definition »Guardian, Five reasons why waiters don’t write down your order,www.guardian.co.uk/lifeandstyle/2011/aug/14/waiters-dont-write-orders-down
WashingtonMay 22-24, 2013Know what you don’t need Necessity vs. sufficiency vs. superfluity “A scientific theory should be as simple as possible, but nosimpler” – Einstein “It is futile to do with more things that which can be done withfewer” – William of Ockham “Not too big, not too small, just right” – Goldilocks« Parsimony »Wikimedia Commons, Goldilocks 1912, commons.wikimedia.org/wiki/File:Goldilocks_1912.jpg
WashingtonMay 22-24, 2013Inclusive applicability Solve a general problem today, to avoid having to solve aspecific problem tomorrow Support for re-configuration or self-configuration Facilitate (re)use, potentially in novel waysCf. Yourdon and Constantine (1979), Structure Design: Fundamentals of a Discipline of ComputerProgramming (Prentice-Hall), www.win.tue.nl/ ~wstomv/ quotes/structured-design.html#19« Generality »Brian Snelson, Lovely new metric spanners and torque wrench,www.flickr.com/photos/exfordy/353771860LoggerHead Tools, Bionic wrench, loggerheadtools.com
WashingtonMay 22-24, 2013The Unix philosophy Make each program do one thing well To do a new job, build afresh rather than complicate oldprograms by adding new features Expect the output of every program to become the input toanother, as yet unknown, program Dont hesitate to throw away the clumsy parts and rebuildthemCf. McIllroy et al. (1978), “Unix time-sharing system: Forward,” Bell Systems Technical Journal 57(6): 1899–1904, www3.alcatel-lucent.com/bstj/vol57-1978/articles/bstj57-6-1899.pdf« Modularity / Granularity / Orthogonality / Emergence »Windell Oskay, Inside-out Lego brick, www.flickr.com/photos/oskay/265899811
WashingtonMay 22-24, 2013Just in case, just in case Plan for failure Replication to avoid single points of failure Decorrelation to avoid cascade failureCf. Rosenthal (2010), “LOCKSS: lots of copies keeps stuff safe,” US Workshop on Roadmap for DigitalPreservation Interoperability Framework, NIST, Gaithersburg, MDlockss.org/locksswiki/files/NIST2010.pdf« Redundancy »Energy Press, PWC: Το δάνειο στο ΛΑΓΗΕ δεν αρκεί για να μην καταρρεύσει η αγοράwww.energypress.gr/news/lianikh-reymatos/PWC:-To-daneio-sto-LAGHE-den-arkei-gia-na-mhn-katarreysei-h-agoraNCinDC, Life is one big balancing act, www.flickr.com/photos/ncindc/3229050640
WashingtonMay 22-24, 2013First make it work, then make it work better Configuration Customization Iterative enhancementCf. May and Zimmer (1996), “Evolutional development model for software,” HP Journal (August): 39-45,www.hpl.hp.com/hpjournal/96aug/aug96a4.pdf« Evolution »Wikimedia Commons, commons.wikimedia.org/wiki/File:Human_evolution_scheme.svg
WashingtonMay 22-24, 2013Easy come, easy go Preservation systems are inherently ephemeral andexpendable; the content managed in them is not Avoid system lock-in Standardized content representation Standardized APIs Smooth migration paths Your (aging) system’s DIP should be a replacement system’s SIP Preferably, change at a time and place of your choosingCf. Janée (2009), “Relay-supporting archives: Requirements and progress,” International Journal of DigitalInformation 4(1), www.ijdc.net/index.php/ijdc/article/view/102« Transience »
WashingtonMay 22-24, 2013Keep the customer satisfied Default system behaviors should conform to implicit userexpectations Know the communities you are seeking to serve Consistency Treat like things alikeCf. Raymond (2003), “Applying the rule of least surprise,” Art of Unix Programming (Addison-Wesley),http://www.faqs.org/docs/artu/ch11s01.html« Least surprise »Narufag, Naruto in the scream, narufag.deviantart.com/art/naruto-in-the-scream-267479366
WashingtonMay 22-24, 2013Commodity, firmness, and delight “Well building hath three conditions: firmness, commodity,and delight” – Vitruvius, De architectura [trans. Wotten, 1694] The analogous conditions for computer, rather than structural,architecture are… Utility Resilience EleganceCf. Madni (2012), “Elegant systems design: Creative fusion of simplicity and power,” Systems Engineering15(3): 347-54, doi:10.1002/sys.21209« Elegance »Dominic 2007, Pantheon Dome, www.flickr.com/photos/9556741@N03/3157684854
WashingtonMay 22-24, 2013Beg, borrow, or steal Learn from the solutions and experience of the community Support the community and contribute backCf. Anderson (2011), “National Digital Stewardship Alliance: Community, content, commitment,” CENDIPrincipals and Alternatives, Washington, DCwww.cendi.gov/presentations/03_06_11_Anderson_Martha_NDSA.pdf« Community »Enrique Martinez Bermejo, Community-manager,www.flickr.com/photos/kikemb/5428414543Duncan Hall, Attention aux PickPockets,www.flickr.com/photos/dullhunk/4575707721
WashingtonMay 22-24, 2013Principles in action: micro-services Decomposition of infrastructure function into a granular set ofindependent, but highly interoperable servicesCf. Abrams, Cruse, Kunze, and Minor (2011), “Curation micro-services: A pipeline metaphor forrepositories,” Journal of Digital Information 12(2), journals.tdl.org/jodi/article/view/1605“Archivematica implements a micro-serviceapproach to digital preservation”http://www.archivematica.org/“Curation Architecture Prototype Services (CAPS), isbuilt on the micro-services approach to digitalcuration” http://www.libraries.psu.edu/“The micro-services approach … seemed similar tothe SDR 2.0 principle of making services moremodular” http://library.stanford.edu/“*SDB] provides a viable solution to the challengesof long term digital preservation by delivering aflexible, extensible set of micro-services”http://www.tessella.com/“The University of North Texas (UNT) hasimplemented a robust architecture for digital libraryinitiatives utilizing the Curation Micro Servicesmethodology for building repository infrastructure”http://www.library.unt.edu/Mode Focus Value Service Valence VisibilityCurationValueAccretion AnnotationUI/Accesscontrol/MessagequeuingInteroperationUser-facingVisibility NotificationUtilityAccessibility AccessApplicationDerivation TransformationSelectivity SearchActionability IndexStewardship IngestPreservationContextEpistemology CharacterizationInterpretationProvider-facingOntology InventoryStateReliability ReplicationProtectionFixity FixityStability StorageIdentity Identity
WashingtonMay 22-24, 2013Design principles for preservation systems Integration Least surprise Definition Elegance Generality Community Parsimony Modularity Granularity Orthogonality Emergence Redundancy Evolution TransienceNote that these are principles, not rulesTheir applicability will depend on localneeds, conditions, expertise, resources,etc.—Rely on your intuition and experiencewww.slideshare.net/UC3/pasig-2013abramsdesignprinciplesforpreservationsystems
WashingtonMay 22-24, 2013UC Curation Center email@example.comStephen Abrams David LoyPatricia Cruse Mark ReyesShirin Faenza Joan StarrScott Fisher Carly StrasserErik Hetzner Marisa StrongJoshua Hubbard Adrian TurnerGreg Janée Bhavitavya VedulaJohn Kunze Kenneth WeissRosalie Lack Perry Willetwww.slideshare.net/UC3/pasig-2013abramsdesignprinciplesforpreservationsystems
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