The OAIS experience at the British Library

Deborah WoodyardDigital Preservation Coordinator

ERPANET OAIS Training Seminar, 28-29 Nov 2002

OVERVIEW

Introduction to the British Library

Why the BL chose to use the OAIS model

OAIS theory versus implementation

Terminology

Metadata

Issues not covered by OAIS

Summary of lessons learned about using the OAIS

THE BRITISH LIBRARY

Deposit library Aiming to get deposit legislation for digital

materials Receiving digital material by voluntary deposit,

purchase and digitisation Wide variety of types of digital material received Require method/system for long term storage,

preservation and access Seriously embarked on developing such a system

in 2000 Initial work developed detailed functional

specification of a system aligned with OAIS model concepts

WHY OAIS?

Very little current experience of a system such as this exists

No ‘off-the-shelf’ systems available No other standards OAIS model well developed Considered to be the guidance for best practice Provided excellent high level framework and

convincing back-up argument for political justification for development of such a system

Provided standard terminology for communication A good match for almost the entire system we

were planning to build

OAIS THEORY vs SYSTEM IMPLEMENTATION

High level standard implies no rules for actual design or implementation

OAIS sounds like one system but is not necessarily, or even likely to be, one single entity

No formal method of implementation used

Analysed business processes and matched to OAIS functions

DIAGRAM COMPARISON

OAIS TERMINOLOGY

Useful as a common vocabulary which is used to communicate with internally and externally

Difficult to explain without reading a lot of the document, therefore opaque to those not heavily involved (e.g. OAIS vs OAI)

Still needed to create another glossary

Especially useful: SIP, AIP, DIP; Ingest; Content Information = Content Data Object +

Representation Information

Difficulties with: defining an object; naming preservation users

OAIS METADATA TO BL METADATA

Packaging Information (i.e. how and where the bits are stored)

Content Information including Representation Information (i.e. how to interpret the bits into data)

Preservation Description Information including Reference Information Context Information Provenance Information Fixity Information

(i.e. how to interpret the data into information)

CONTENT INFORMATION

Representation Information (Content data object description)

Technical details of files and resource structure How the resource appears, is installed and runs Documentation Significant properties

Representation Information (Environment description)

Requirements for hardware, peripherals, Operating system, application software, Input and output, memory requirements and other

parameters Documentation on installation, use and location of

environment components.

PRESERVATION DESCRIPTION INFORMATION

Reference Information Identifiers & descriptive information

Context Information Reason for creation, relationships with other

resources

Provenance Information Origin of the resource & changes made due to

its life in the archive

Fixity Information Authentication details

BL METADATA (1/8)

Agent Group Agent Identifier

Agent Role Personal Agent

Group Personal Agent Name

Affix Personal Agent

Family Name Personal Agent Given

Name Personal Agent

Affiliation, Personal Agent Vital

Date

Corporate Agent Group Corp Agent Name Corp Agent Place

Event Agent Group Event Agent Name Event Agent Number Event Agent Location Event Agent Date

Other Agent Group Other Agent Name Other Agent

Description

BL METADATA (2/8)

Descriptive Items Group Language Page Range Frequency Of Serial Issue Data Audience

Title Group Primary Title Title Status Alternative Title Sub Title Series Title Series Title Number Article Title Uniform Title

BL METADATA (3/8)

Subject Group LCSH DDC Name As Subject Free Text Other Subject

Vocabularies BL Collection BL Classification

Description Group Abstract Table of Contents Map Scale Free Text

BL METADATA (4/8)

Date Group Date Issued Date Available Date Created Date Archived Licence Check Date Date Modified Date Coverage Date Valid Vital Date Event Date Other Descriptive

Dates System Dates

BL METADATA (5/8)

Coverage Group Temporal coverage Spatial Coverage

Terms Group Price Terms Of Availability

Statement Terms Of Availability

Reference

Type and Identifier Group

Resource Type Object Type Object Preservation

Category Resource Identifier System IDs Descriptive IDs

Format Group

BL METADATA (6/8)

Relation Group Relation Is Version Of Relation Is Format Of Relation Is Part Of

Relation Is Component Of

Relation Is Replaced By

Relation Replaces Relation Requires Relation External

Object Relation Continues

History Group Custody History Digitisation History Ingest History Preservation History

Process Name Process Description Process Reason Process Selection Process Specification Critical Hardware Critical Software Process Result Process Agent Process Date

BL METADATA (7/8)

Object Part Group Digital Signature Digital Signature

Name Operating

Environment Object Part

Preservation Status Viewing Software Object Part Identifier Start File Underlying Abstract

Form Essence of Being

External Object Group Source Relation External Object Related Information

Object Other

Original Environment Group

Operating System Processor Type Processor Speed Hard Disc Capacity RAM Video Card Sound Card CD Speed

BL METADATA (8/8)

Rights Information Group

Rights Group Rights URL Rights XRML Rights Statement

Rights Holder

Licence Group Licence Type Licence Fee Licence Description Location Number Of Licences

System Parameter Group Licence Key Extraordinary

Requirements Original Carrier Copy Counter

ISSUES NOT COVERED BY THE OAIS (1/3)

Boundary of the system under development: Which materials will be stored in this system Should descriptive information be stored

internally Should object relationships be stored internally Should a retrieval manager component be

included Should an exit strategy (high volume data

transfer) be built from day one

Changes to metadata:

Should changes be allowed without delivery and re-ingest as new item

ISSUES NOT COVERED BY THE OAIS (2/3)

Object deletion: Not included and may be difficult to implement Remove content or only access to content

Object identification in a volume: In the case of corruption or requested

refreshment is it necessary to be able to identify the individual object on a volume

Independent use of archive volumes: Disaster recovery without exact same system

ISSUES NOT COVERED BY THE OAIS (3/3)

Unique identifier: Where should it be generated What structure should it have

How to store license information: Scan hard copy or data entry Where should it be stored

Data integrity: How often should the data be checked

SUMMARY OF MAIN LESSONS LEARNED

It’s heavy

It’s complex

It doesn’t define your scope

It’s worth understanding the terminology and concepts

It is a very valuable tool and the basis of progressing the long term preservation of digital information