1. Final Exam Review
CptS 464/564
April 25, 2018

2. Distributed Systems Paradigms: © 2008-2018 David E. Bakken
Overview
First: Please do course evaluations!
myWSU portal
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Exam
Monday April 30, 8:10-10:00am
Same rooms unless I tell you otherwise by
Final is NOT comprehensive
But don’t forget everything you learned for the midterm
Exceptions
Local vs. Remote call in first day intro slides, what a proxy is, etc
Basics of GridStat (routing overlays)
Compared to midterm
110/75 of the time
Reminder: CptS 562 (Fault-Tol. Comp.) in 1035
CptS 464/564 Fall
Distributed Systems Paradigms: © David E. Bakken

3. Distributed Systems Paradigms: © 2008-2018 David E. Bakken
Overview(2)
Main Categories in Final Exam (not chronological)
Chapter 4: Interprocess Communication (IPC)
Chapter 5: Remove Invocation
Chapter 6: Indirect Communication
Chapter 10: Peer-to-Peer
Chapter 15: Coordination and Agreement
CORBA
CptS 464/564 Fall
Distributed Systems Paradigms: © David E. Bakken

4. Chapter 4: Interprocess Communication
API for Internet protocols
Basic ideas/functionality, compared to middleware
NOT the detailed syntax of socket API
External data representation and marshalling
Multicast communications
Network virtualization: overlay networks
Case Study: MPI
NOT covered so NOT on exam for 464
564 responsible for reading it
CptS 464/564 Fall
Distributed Systems Paradigms: © David E. Bakken

5. Chapter 5: Remote Invocation
Request-reply:
low-level client-server interactions
built on top of message send and receive ops (Ch4)
Remote Procedure Call (RPC)
Make a remote procedure look (almost) like a local one to call (what does this entail?)
Call semantics (VERY IMPORTANT)
Remove Method Invocation (RMI)
Make a remote object look (almost) like a local one to invoke
Note: ‘RMI’ is generic category, Java RMI is a specific instance
What is a lease, and how/why is it used? Alternative?
Not covering Java RMI: nobody needs to know this
CptS 464/564 Fall
Distributed Systems Paradigms: © David E. Bakken

6. Chapter 6: Indirect Communication
Context ….. Time and space uncoupling
Group communication
Niche/purpose, main abstraction, main properties/mechanisms, different “flavors” (open vs. closed group, etc)
NOT JGroups example details/syntax: just there to make concrete the concepts we discuss
Publish-subscribe systems
Main ideas, niche/purpose, different flavors, … implementation choices & tradeoffs
Message queues
Main ideas, niche/purpose, contrasted with pub-sub & group comm, IBM Websphere
JMS NOT testable: there to reinforce concepts
Distributed Shared Memory: basic ideas, contrast w/above
CptS 464/564 Fall
Distributed Systems Paradigms: © David E. Bakken

7. Chapter 10: Peer-to-Peer Systems
Big picture: why do they exist?
Napster and its legacy
Peer-to-Peer Middleware (3G P2P)
Goals, requirements, etc
Routing Overlays
What they are, purpose, etc
Comparing and contrasting text’s with GridStat’s
Case Studies
Pastry
Tapestry
Runtime issues: handling failure (or lack thereof), load balancing, background maintenance, …
Unstructured P2P basics, contrasted with structured
Basics of Squirrel, OceanStore
CptS 464/564 Fall
Distributed Systems Paradigms: © David E. Bakken

8. Introduction to DSs: © 2016 David E. Bakken
Testability (cont.)
Chapter 15: Coordination and Agreement
15.2: Distributed mutual exclusion
15.3: Elections
6.1 Overview of Indirect Communication
6.2 Intro to Group Communication
15.4: Group communication (and coord./agreement with it)
Programming Projects
Basics/Lessons from pub-sub
CptS 464/564 Spring 2016
Introduction to DSs: © 2016 David E. Bakken

9. Introduction to DSs: © 2016 David E. Bakken
Testability (cont.)
CORBA/QuO (you might need to google a little or poke around omg.org if you did not take reasonable notes)
Basic features
What is an IDL language mapping?
Exceptions: system vs. user-defined
System hooks
Smart stub (vs. SII proxy vs. QuO Delegate)
Interceptors (why 4 in the call path?)
CptS 464/564 Spring 2016
Introduction to DSs: © 2016 David E. Bakken