CS 5523 Operating Systems Midterm Review
Spring 2002

The midterm exam will cover Chapters 2 through 6 of CDK. This is a closed book exam. Questions about network communication and Java will not require exact syntax. You should not spend time studying either Stevens or the Core Java books; these are for your reference during implementations of the projects. The following outline is provided as a study guide. You should also review the end-of-chapter questions. Do not expect either the questions asked here or the end-of-chapter questions to be on the exam in the same form. Rather, I will try to come up with questions that test your understanding of these concepts.

System models and fundamental models (Chapter 2)
- System architectures:
- What is the difference between a fundamental model and an architectural model?
- Synchronous versus asynchronous communication and how this affects interaction.
- Event ordering and types of events for different types of communication channels.
- Different types of failure models and how they impact program behavior.
- No questions on security or naming
Networks and communication (Chapters 3 and 4)

How do the characteristics of networks (performance, scalability, reliability, security, mobility, quality of service) affect the OS and applications?
Given a topology and information about latency, transfer rate, and message sizes, you should be able to estimate the time it takes to process requests across a network.
Understand connection-oriented and connectionless protocols. How are connections actually achieved on current networks?
Understand how TCP and UDP work.
Know the steps involved in establishing and using communication in using TCP and UDP (you don't need to know details of parameters for system calls, but rather what needs to be done).
Understand the difference between TCP, UDP and IP.
Understand how packets are routed on the internet (not detailed routing algorithms).
Have a basic understanding of how firewalls work.
Interprocess communication in Java and Unix.
Be able to draw a state diagram for a communication protocol.
Be able to draw a timing chart for message exchanges in a protocol (time lines for the participants that are interconnected).
No OSI layers, IP routing algorithms, mobileIP, IPv6, Ethernet (beyond a basic understand of the ideas), ATM.

Communication above the network layer (Chapters 4 and 5)

The object model and distributed objects?
What is middleware and what is it good for?
What is remote invocation?
What is an RPC?
What is marshalling, why is it needed and how is it accomplished?
How do remote references work?
What is serialization? Reflection?
Different models of client-server communication (request, request-reply, request-reply-acknowledge).
Where these models might be used
What kind of behavior is expected when R, RR or RRA are used over TCP? over UDP?
How are timeouts, history and message sequencing used in the implementation of these client-server communication protocols?
HTTP
Java RMI
No group communication, Sun RPC details, Corba, multicast, group communication, events, JINI.

Operating System Support (Chapter 6)

OS architectures - monolithic versus kernel.
Thread architectures - user-level, kernel-level and hybrid?
What resources are per-process? Per-thread?
How does thread execution work for user-level threads? For kernel-level threads?
Tradeoffs between using multiple threads and multiple processes for implementing servers.
Thread organizations - thread-per-request, worker-pool, thread-per-object.
Invocation performance.
Asynchronous operation of invocation mechanisms.

There may be specific questions on Laboratory 1.
Last revision: March 2, 2002 at 10:10 am

CS 5523 Operating Systems Midterm Review Spring 2002

CS 5523 Operating Systems Midterm Review
Spring 2002