Protection and Synchronization in Actor Systems
Name
AI_WP_083.pdf
Description
Main article
Size
1.01 MB
Format
Adobe PDF
Checksum (MD5)
748d04b824ca9be291e930371f45c41f
Author(s)
Hewitt, Carl
Date Issued
November 1974
Publisher
MIT Artificial Intelligence Laboratory
Series/Report no.
MIT Artificial Intelligence Laboratory Working Papers, WP-83
Abstract
This paper presents a unified method [called ENCASING] for dealing with the closely related issues of synchronization and protection in actor systems [Hewitt et al. 1973a, 1973b, 1974a; Greif and Hewitt 1975]. Actors are a semantic concept in which no active process is ever allowed to treat anything as an object. Instead a polite request must be extended to accomplish what the activator [process] desires. Actors enable us to define effective and efficient protection schemes. Vulnerable actors can be protected before being passed out by ENCASING their behavior in a guardian which applies appropriate checks before invoking the protected actor. Protected actors can be freely passed out since they work only for actors which have the authority to use them where authority can be decided by an arbitrary procedure. Synchronization can be viewed as a [time-variant] kind of protection in which access is only allowed to the encased actor when it is safe to do so.
Subjects
protection
synchronization
actors
data base access
data definition languages
Persistent DSpace Link
