shapiro@xombul.inria.fr (Marc Shapiro) (03/21/91)
The following Technical Report is available: -------------------------------------------------------------------- STRUCTURING DISTRIBUTED APPLICATIONS AS FRAGMENTED OBJECTS Mesaac Makpangou, Yvon Gourhant, Jean-Pierre Le Narzul, Marc Shapiro Rapport de Recherche INRIA 1404 February 1991 Abstract Most distributed systems offer only primitive communication objects (e.g. channels). Their undisciplined use obscures, and exposes the implementation of, higher-level concepts. We propose instead a high-level, structured approach, called Fragmented Objects. A Fragmented Object is a distributed shared object. Clients see a fragmented object as an ordinary object. The implementor of a fragmented object decides of its interface and representation, including (if necessary) aspects such as placement of data items, communication between fragments, protocol layering, and binding. The fragmented object model provides a common framework for different distribution mechanisms, such as client/server stubs, replication, cacheing, and data partitioning. We present the basic fragmented object concepts and a full example, the SOS Naming Service, layered into Name Space and Naming View objects. Each of these layers is implemented as fragmented objects; we point out specific benefits of the fragmented object approach. We have defined a fragmented-object language called FOG, a compiler, and a toolkit of primitive fragmented objects. The compiler enforces encapsulation, checks interface consistency, and generates hooks to the toolkit. The compiler and the toolkit facilitate the most common distribution policies. ---------------------------------------------------------------------- To obtain a paper copy, send e-mail with you name and address (and saying what you want) to <nelly@sor.inria.fr>. It is also available by anonymous FTP: machine: nuri.inria.fr [128.93.1.26] login: ftp password: your own e-mail address mode: binary directory: local/INRIA-publication file: RR-1404-dvips.tar.Z or: RR-1404.ps.Z The first file is in DVI format with PostScript figures (tarred and compressed). It is attested to work with recent versions of Rockiki's `dvips', and should probably work with other dvi-to-ps drivers. Give preference to this file if possible. The second is entirely (compressed) PostScript. It will print on a LaserWriter II NTX. No guarantees are given on other printers. Sizes: -r--r--r-- 1 shapiro 62541 Mar 19 11:31 RR-1404-dvips.tar.Z -r--r--r-- 1 shapiro 121027 Mar 19 11:31 RR-1404.ps.Z -- Marc Shapiro INRIA, B.P. 105, 78153 Rocquencourt Cedex, France. Tel.: +33 (1) 39-63-53-25; fax: +33 (1) 39-63-53-30; e-mail: shapiro@sor.inria.fr