Changes for Preservation Policy Metadata concerning preservation Level

Changes for Preservation Policy Metadata concerning preservation. Level entity Eld Zierau The Royal Library of Denmark PREMIS implementation Fair 2014 Melbourne, oct. 6, 2014

Overview Challenge: § Preservation Policy Metadata – ◦ How to express sustainable preservation policies ◦ How to record these (in PREMIS) PREMIS change: § Allows the preservation policy applied to preserved digital objects to be recorded in more detail by updating the preservation. Level semantic container. PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 2

Contents of this presentation § Preservation Strategies and policies ◦ On logical/functional level ◦ On bit preservation level § Challenges ◦ Expressing preservation levels ◦ Preserving preservation metadata ◦ Expressing preservation levels over time § An example on the bit level ◦ Risks mitigated in bit preservation ◦ Bit integrity/safety, confidentiality and availability § Types of preservation Levels ◦ How to express them – also over time § Summary PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 3

Preservation Strategies & Policies § Logical preservation ◦ Migration ◦ Emulation Digital preservation Logical preservation Bit preservation ◦ Technology preservation PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 4

The Change from 2. 2 to 3. 0 Information indicating the decision or policy on the set of preservation functions to be applied to an object and the context in which the decision or policy was made. Semantic unit Semantic components 1. 3 preservation. Level 1. 3. 1 preservation. Level. Value 1. 3. 2 preservation. Level. Role 1. 3. 3 preservation. Level. Rationale 1. 3. 4 preservation. Level. Date. Assigned Semantic unit Semantic components 1. 3 preservation. Level 1. 3. 1 preservation. Level. Type 1. 3. 2 preservation. Level. Value 1. 3. 3 preservation. Level. Role 1. 3. 4 preservation. Level. Rationale 1. 3. 5 preservation. Level. Date. Assigned PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 5

Logical Preservation Value Comment for preservation. Level. Type = logical. Strategy Migration of digital material to keep data interpretable Emulation of digital material to keep data interpretable Technical Technology preservation to keep data interpretable PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 6

Preservation Strategies & Policies � Bit preservation Digital preservation 010110001000 Logical preservation e s e r p it B in ts Elemen Risk mitigation in Bit pres ervation Bit preservation ISO 27000 series – at a higher level Integri ty (Bit Avail safety ) Confi abilit y Costs dentia lity PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 7

A General View of a Bit Repository Elements in bit preservation: Number of copies § Independence between copies § Frequency of integrity checks § Bit sequences ues q i n h c & te n and o i t d a e s i g n n Orga d and arra e bit design long-term or used f tion rva prese eck h c y t i r g e Int tion Coordina Bit Repository General System Layer Pillar 1 Pillar 2 Pillar 3 Layer Pillar 4 Pillar 5 Pillar 6 Pillar 7 Pillar 8 … PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 8

Integrity – Bit error Risk: Bits can change value 1. Error has occurred in Backup 2. File is corrupted 3. Error is not discovered 4. Cannot determine which file is intact File in form of bit stream Solutions: 1. No backup. All are copies of data 2. Vote on which copy that is the right one PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 9

Bit error – System Layer Bit Repository (BR) System Layer Pillar Layer … Solutions: 1. System layer checks and follow-up on basis of comparing copies 2. Minimum three voters, optimize by checksums PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 10

Integrity – Bit error Risk: Bits can change value 1. Error has occurred in Backup 2. File is corrupted 3. Error is not discovered 4. Cannot determine which file is intact File in form of bit stream A 0953 B 7 Solutions: 1. No backup. All are copies of data 2. Vote on which copy that is the right one 3. Introduce checksums of files to discover errors PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 11

Integrity – Bit error Risk: The same error occurs for more copies 1. Same hardware 2. Same software 3. Same vendor PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 12

Integrity – Bit error Risk: The same error occurs for more copies 1. Same hardware 2. Same software 3. Same vendor Unix … Windows … Mac …OS Solutions: 1. Different hardware solutions 2. Different vendors 3. Different software (OS, interpreters, etc. ) PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 13

Integrity – Disasters Risk: All copies are damaged at the same time 1. Natural disasters 2. Attacks in connection with war or terror PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 14

Integrity – Disasters Risk: All copies are damaged at the same time 1. Natural disasters 2. Attacks in connection with war or terror Solutions: 1. Different geographical locations PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 15

Integrity – Organisation Risk: Errors/mistakes are made by the same person/org. 1. The same person has access and has delete rights 2. The same person makes procedural mistakes PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 16

Integrity – Organisation Risk: Errors/mistakes are made by the same person/org. 1. The same person has access and has delete rights 2. The same person makes procedural mistakes Solutions: 1. Different organisations PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 17

Confidentiality Risk: Unauthorised gets access to confidential data 1. Unauthorised gets access to Bit Repository 2. Unauthorised gets access to data from Bit Repository Encryp tion ca n conflic t integr ity A 0953 B 7 Solutions: 1. Authentication of users of pillars with copies 2. Encryption internally on pillar 3. Hardware secured in locked rooms PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 18

Confidentiality – System Layer Bit Repository (BR) System Layer … Pillar Layer … A 09537 Likewis e System on layer PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 19

Availability Risk: Cannot get access as required 1. Cannot get any response on request 2. Processing not possible in reality Proces si confide ng can confl ict n and bit tiality safety Solutions: 1. Specialised pillar with distributed architecture PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 20

Availability Bit Repository (BR) System Layer … Pillar Layer … Solutions: 1. Redirection if access to a pillar is down 2. Distributed requests to different pillars Scaling Diversity, 5. … 3. 4. PREMIS Workshop at i. Pres 2014, Melbourne, Australia at h w on s d n e Dep uired q is re Preservation Policy Metadata Slide 21

Bit Repository – Different Current Solutions BR General System Layer Pillar 1 Pillar 2 Pillar 3 Pillar 4 Layer Pillar 5 Pillar 6 Pillar 7 Pillar 8 Pillar 9 … § § § § Media Data safety Access speed On-line Off-line Organisational placement Geographical placement … Av Bit Cos aila safe ts bili ty ty Con fide ntia lity PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 22

Bit Safety Value Comment for preservation. Level. Type = Bit. Safety Maximum bit safety Very. High Very high bit safety High bit safety Medium bit safety Low bit safety Very. Low Very low bit safety Minimum bit safety PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 23

Bit Safety Value Comment for preservation. Level. Type = Bit. Safety Maximum bit safety Very. High Very high bit safety High bit safety Medium bit safety Low bit safety Very. Low Very low bit safety Minimum bit safety Policy: As high bit safety that we can get Strategy 2014: 10 copies spread over 3 continents, both optical and magnetic medias, checked every … Strategy 2050: 8 copies ; at lest 2 on Mars, at least two written to DNA, checked every … PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 24

Confidentiality Value Comment for preservation. Level. Type = Confidentiality Maximum confidentiality Very. High Very high confidentiality High confidentiality Medium confidentiality Low confidentiality Very. Low Very low confidentiality Minimum confidentiality PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 25

Confidentiality Value Comment for preservation. Level. Type = Confidentiality Maximum confidentiality Very. High Very high confidentiality High confidentiality Medium confidentiality Low confidentiality Very. Low Very low confidentiality Minimum confidentiality Policy: Only restricted access, where it is as hard as it can get for others when skipping encryption Strategy 2014: No more than 2 copies, that are secured on off-line medias … Strategy 2050: ? ? ? … PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 26

Availability Value Comment for preservation. Level. Type = Availability Maximum availability Very. High Very high availability High availability Medium availability Low availability Very. Low Very low availability Minimum availability … PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 27

Preservation Level in metadata <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value>bit. Safety. High</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 458+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value>confidentiality. Low</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 460+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value>availability. Medium</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 460+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 28

Preservation Level in metadata <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value>bit. Safety. High</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 458+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value>confidentiality. Low</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 460+01: 00 <preservation. Level xmlns: xlink="http: //www. w 3. …”> </preservation. Level. Date. Assigned> <preservation. Level. Type>bit. Safety</preservation. Level. Type> </preservation. Level> <preservation. Level. Value> High</preservation. Level. Value> <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value> availability. Medium <preservation. Level. Date. Assigned > </preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 460+01: 00 2013 -01 -18 T 19: 28: 01. 458+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 29

Preservation Level in metadata <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value>bit. Safety. High</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 458+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value>confidentiality. Low</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 460+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value> </preservation. Level. Value> <preservation. Level availability. Medium xmlns: xlink="http: //www. w 3. …”> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 460+01: 00 <preservation. Level. Type>confidentiality</preservation. Level. Type> </preservation. Level. Date. Assigned> <preservation. Level. Value>Low</preservation. Level. Value> </preservation. Level> <preservation. Level. Date. Assigned> 2013 -01 -18 T 19: 28: 01. 458+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 30

Preservation Level in metadata <preservation. Level xmlns: xlink="http: //www. w 3. …”> <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Type>availability</preservation. Level. Type> <preservation. Level. Value> bit. Safety. High</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 458+01: 00 <preservation. Level. Value>Medium</preservation. Level. Value> </preservation. Level. Date. Assigned> </preservation. Level> 2013 -01 -18 T 19: 28: 01. 458+01: 00 <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> </preservation. Level. Date. Assigned> <preservation. Level. Value>confidentiality. Low</preservation. Level. Value> </preservation. Level> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 460+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> <preservation. Level xmlns: xlink="http: //www. w 3. org. 1999/xlink" xsi: …”> <preservation. Level. Value>availability. Medium</preservation. Level. Value> <preservation. Level. Date. Assigned>2013 -01 -18 T 19: 28: 01. 460+01: 00 </preservation. Level. Date. Assigned> </preservation. Level> PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 31

Preservation Level information preservation. Level. Type Comment Bit safety Bit preservation Confidentiality Bit preservation Availability Bit preservation Logical Preservation Strategy Logical Preservation … � Policy � With Types a nd value institution preservation policies � Express values - Same over time � Strategy � Requirements for fulfilment with current technologies … PREMIS Workshop at i. Pres 2014, Melbourne, Australia s can di Preservation Policy Metadata ffer Slide 32

Questions and Comments PREMIS Workshop at i. Pres 2014, Melbourne, Australia Preservation Policy Metadata Slide 33