1. 1 herbert van de sompel CS 502 Computing Methods for Digital Libraries Cornell University – Computer Science Herbert Van de Sompel herbertv@cs.cornell.edu Lecture 17 Access Management

2. 2 herbert van de sompel Users Digital objects Identification & authenticity Attributes Authentication Roles Permitted Operations Laws and agreements Policies Authorization Information Managers Access

3. 3 herbert van de sompel The Access Management Problem The manager of an information collection provides access to materials subject to policies Library – donor restrictions, privacy, copyright Medical records – need to know in certain context Government – secrecy and classification Vendor – payment

4. 4 herbert van de sompel Copyright United States copyright law: To guarantee that there are incentives to create new works Applies to literary works e.g., text, photographs, computer programs, musical scores, videos, audio tapes Initially, the creator of a work or the employer of the creator owns the copyright Exception: materials created by government employees Intellectual property -> can be bought and sold like any other property -> a creator can reassign copyright to a third party

5. 5 herbert van de sompel Copyright Copyright gives the owner the exclusive right to: reproduce distribute perform display license to others Nominally for a fixed period (cf Gutenberg project), but the period has been steadily lengthened

6. 6 herbert van de sompel Copyright Rights of users of copyrighted materials First sale e.g., can sell used books Fair use e.g., can quote short sections in scholarly articles or reviews (cf. OpenContent license) International differences -- moral rights In Canada, France, Belgium,...: author has rights to - attribution of authorship (intellectual ownership) - integrity (cf. colorization of movies ) Moral rights cannot be transferred

7. 7 herbert van de sompel Fair use Factors to consider the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes the nature of the copyrighted work the amount and substantiality of the portion used in relation to the copyrighted work as a whole the effect of the use upon the potential market for or value of the copyrighted work cf. Publish or Perish (scholar can not distribute his own writings to students)

8. 8 herbert van de sompel Contracts, licenses Contracts allow intellectual property to be sold or licensed by copyright owner Almost any terms and conditions can be agreed -> Can ignore “fair use” issues -> Permanent or temporary, whole or part -> Exclusive or non-exclusive -> Restrictive license or broad Enforceable by courts This becomes a trend regarding digital information: libraries no longer buy information but buy a license that allows access to information => no guaranteed long-term access!

9. 9 herbert van de sompel Users Digital objects Identification & authenticity Attributes Authentication Roles Permitted Operations Laws and agreements Policies Authorization Information Managers Access

10. 10 herbert van de sompel Digital objects Identification & authenticity Attributes Authorization

11. 11 herbert van de sompel Digital objects Digital objects contain information that users may wish to access. Access to the digital object is subject to policies (see earlier). Policy-related properties of the digital objects that are important for access are encoded as attributes.

12. 12 herbert van de sompel Digital objects: attributes Attributes Administrative metadata that describes policy- related properties of the digital object, e.g. Registered for copyright on 1/1/1996. French government publication. Letter from donor, dated 1/1/1893, states "I donate my collected papers to the nation." In real-life: In many cases attributes are expressed at the level of collections. Objects inherit the attributes. BUT...

13. 13 herbert van de sompel Permitted Operations Digital object Gaudeamus igitur Juvenes dum sumus Attributes Different attributes may be associated with different elements of a digital object. Authorization Complex digital object

14. 14 herbert van de sompel Users and roles Users Authentication Roles Authorization Roles

15. 15 herbert van de sompel Users and roles User A user is a computer system, or a person using a computer system, wishing to access digital objects. Characteristics of users are encoded as roles. The same user can have different authorizations regarding access to digital objects, depending on the role.

16. 16 herbert van de sompel Users and roles Roles Verifiable facts about a user, used in access management, e.g., The user is a subscriber to all ACM publications. The user is a faculty member at University X. The user is a student at High School Y. The user is physically located within the Library of Congress. A user can have different roles simultaneously

17. 17 herbert van de sompel Users and roles: theory authentication roles-dbase roles 110010110 101100101 101010000 attributes

18. 18 herbert van de sompel Users and roles: reality authentication role attributes 110010110 101100101 101010000 collection

19. 19 herbert van de sompel Permitted operations Permitted Operations Access Roles Authorization The result of the authorization process, is a certain access-level: permitted operations. How to enforce those?

20. 20 herbert van de sompel Permitted operations Formally defined actions that a user may take to access digital objects, e.g., Replicate from one computer to another.. Listen to a recording twice Render an image on a screen. Extract 2 minutes from a video program. Create a derivative work. Perform in public for profit. Export to Australia.

21. 21 herbert van de sompel Permitted operations: enforcement? Enforcement Methods to ensure that the permitted operations are the only actions carried out on digital objects. Enforcement may be: technical (e.g., encryption) IBM Cryptolope, LiquidAudio, legal (e.g., damages for violation) contractual (e.g., revocation of license) social (e.g., isolation from peers) need detection mechanism - Relatable audio identifiers {