CMSC 433, Alan Sussman, U. Maryland (via
Bill Pugh) 1
CMSC433, Spring 2001
Programming Language
Technology and Paradigms
Distributed Computing
Alan Sussman
October 30, 2001
CMSC 433, Fall 2001 -Alan Sussman 2
Administrivia
•Grading info for Project 2 posted today
•Commentary for Project 3 due Wednesday,
November 14
–programs sent out yesterday
–questions about Project 3 design?
•Project 4
–due next Wednesday, November 7
•Read Ch. 15, pages 980-989, in Eckel
–Readings web page also has additional distributed
computing and CORBA readings
CMSC 433, Fall 2001 -Alan Sussman 3
Last time
•RMI
–Stubs
–Remote objects and interfaces
–RMIregistry
•for bootstrapping (Naming.lookup(), Naming.bind())
CMSC 433, Fall 2001 -Alan Sussman 4
Is distributing computing
different?
•What kinds of distributed computing
environments exist?
•Ways in which distributed computing is
different
–Addressing objects
–Latency
–Partial failure
–Concurrency
CMSC 433, Fall 2001 -Alan Sussman 5
Distributed computing
environments
•Usually refers to multiple CPU’s
•Interprocessor communication via shared
address space or message passing?
•On same chip, in same room, or across the
Internet?
–latency, failure modes
CMSC 433, Fall 2001 -Alan Sussman 6
Existing environments
•Seti @ Home, Entropia
•Server for search engine
•My laptop, PDA, cell phone, MP3 player,
digital camera, …
