CSC 420 Homework

Homework #8 (the final HW!) due Tuesday May 28, 2002

Assignment:

Problem 18.1 - definitions

Problem 18.11 - "need to know" principle

Ch 18 - Unix protection

What is the difference between having a file's setuid bit in Unix "on" and "off"? Give an example of a program that you (a regular user, not superuser) might create where the setuid bit is on.

Ch 19 - system threats

What is the difference between a worm and a virus? Which is a more dangerous threat to system security?

Ch 19 - Windows NT security

Describe 3 security features in Windows NT.

My solution: HW #8 Solution

Homework #7 due Tuesday May 21, 2002

Assignment:

	Problem 13.8 - DMA (5 pts)
	Problem 14.2 - disk scheduling algorithms (10 pts)
	Problem 14.9 - disk scheduling trivia (5 pts)

My solution: HW #7 Solution

Homework #6 due Tuesday May 14, 2002

Assignment:

	Problem 11.6 - single level directory structures
	Problem 11.12 - Unix protection schemes
	Problem 12.9 - Caches
	Problem 12.11 - dynamic allocation issues

My solution: HW #6 Solution

Homework #5 due Tuesday May 7, 2002

Assignment:

	Problem 9.2 - explain fragmentation
	Problem 9.5 - first-fit, best-fit, worst-fit memory allocation comparison
	Problem 9.8 - calculating address sizes
	Problem 9.16 - determining addresses for a segment table... hint: the first digit in the address is the segment.
	Problem 10.2 - theoretical page faults... hint: remember that frames are initially empty, so filling them is a page fault each time
	Problem 10.11 - simulate LIFO, LRU and Optimal page replacement algorithms. NOTE: only simulate the reference string using 5 available frames, not all seven cases. Show each algorithm with 5 available frames.

My solution: HW #5 Solution

Homework #4 due Tuesday April 30, 2002

Assignment:

Show each event (or interrupt) for the "data2002.txt" data set from Program #1. An event is:

	I/O request
	I/O completion
	Time slice completion
	Process CPU completion

At each event, please show the system clock, what process is on the CPU, the Ready queue, the processes doing I/O, and the amount of CPU so far for each process.

I'll get you started... here's system clock time 0-20:

					Cpu so far
Time	Intr	CPU	ReadyQ	IOList	P1	P2	P3	P4
0	n/a	1	2, 3, 4		0	0	0	0
10	IO Req	2	3, 4	1@90	10
20	Time slice	3	4, 2	1@90		10

I recommend creating an Excel spreadsheet to complete this homework; it's easiest. I'll accept any medium I can read on your k: drive however. BTW, I had about 45 interrupts in my solution.

Also, you can see the correct process completion times my solution to Program #1 on the k: drive.

If your solution to data2002.txt in Program #1 got the correct completion times, then you have already earned your 10 points for this half-homework. Or in other words, you got a 4/4 for the data2002 part of your Program #1 grade.

My solution: HW #4 Solution

Homework #3 due Tuesday April 16, 2002

Assignment:

Problem 7.2 - spinlocks

Problem 7.7 - semaphores

From section 7.8 on synchronization in Solaris and Windows 2000:

	Solaris: What is an adaptive mutex and how does it work?
	Windows 2000: What are dispatcher objects and how do they work?

Problem 8.4 - deadlock in a traffic jam

Problem 8.13 - the (dreaded) Banker's algorithm (just kidding, it's not that bad)

My solution: HW #3 Solution

Homework #2 due Tuesday April 9, 2002

Assignment:

	Problem 4.2 - scheduling comparison
	Problem 5.3 - user threads versus kernel threads
	Problem 5.6 - processes versus threads
	Problem 6.3 - scheduling algorithms
	From Chapter 5, please describe three "important" facts/properties of the implementation of threads on a) Solaris, b) Windows 2000, c) Linux, and Java operating systems.

My solution: HW #2 Solution

Homework #1 due Tuesday April 2, 2002

Assignment:

1.9 - multiprocessing

2.5 - privileged instructions

3.1, 3.2, 3.4 - OS definitions

Definitions: for each chapter select the "n" most important definitions:

	Chapter 1 - give me your top ten definitions
	Chapter 2 - top ten again
	Chapter 3 - just the top five

The textbook usually highlights (in bold font) newly defined terms, so that should help you. BTW, this ain't an English class, so sentence fragments and phrases are fine.

My Solution: HW #1 Solution

I also have two other special tidbits for you... Please:

Rename your folder on the k: drive to

You select the separator; I just want an alphabetical folder listing.

Please email me. I like to have y'alls email so that I can contact you if needed. Please include your name in the email, eh.

Finally, you have two homework hand-in options: 1) old-fashioned piece of paper, or 2) put your homework on the k: drive as a Word or HTML or text file.