Computer and Number Systems
1. (10 pt) You have been hired to develop a website-based sales system for a large international retail firm. List and describe at least four features that are specific to the Web design of your system and customer service important to consider if your system is to be successful at attracting and keeping customers living outside of the US. Include not only characteristics of the user interface, but those issues that must be uniquely addressed to successfully service your non-US customers.
2. (10 pt) Define memory cache write-through and write-back techniques and describe the advantages and disadvantages of each. Input / Output
3. Answer the follow questions about interrupts.
a. (5 pt) Describe in detail the steps that occur when a system receives an interrupt.
b. (5 pt) Describe how these steps differ in the case when a system receives multiple interrupts Computer Systems
4. Answer the following questions about clusters.
a. (5 pt) Describe how you might use a cluster to provide fault-tolerant computing
b. (5 pt) Describe how you might use a cluster architecture to provide rapid scalability for a Web-based company experiencing rapid growth. Networks
5. Answer the following questions about communication protocols.
a. (5 pt) Using the operations of UDP (User Datagram Protocol) and TCP (Transmission Control Protocol) as a basis, carefully
b. (5 pt) If you were ordering a number of items from an online seller, such as amazon.com, which Protocol (TCP or UDP) would you recommend and explain why.
6. In the context of network security,
a. (3 pt) explain the purpose of non-repudiation.
b. (3 pt) How does non-repudiation differ from authentication?
c. (4 pt) Create a business scenario that illustrates the importance of each.
7 Operating Systems
Answer the following questions about user interfaces:
(a) (5 pt) List and explain at least two of the definite advantages to the use of a command line interface (CLI) over other types of interfaces.
(b) (5 pt) There are some capabilities that are easy to achieve with a GUI (graphical user interface), but much more difficult with a CLI. Describe at least two of these capabilities.
8. File Management
a. (5 pt) Use the following four processes that have arrived in the ready queue in the sequence shown below and answer the following about process scheduling:
• Process 1 has a total run time of 25 seconds and a priority of 2, but it will require 15 seconds of I/O after 10 seconds of execution
• Process 2 has a total run time of 30 seconds, a priority of 1, but it will require 10 seconds of I/O after 20 seconds of execution
• Process 3 has a total run time of 15 seconds and a priority of 3
• Process 4 has a total run time of 20 seconds, a priority of 2, but it will require 15 seconds of I/O after 5 seconds of execution
(i) Both shortest job first and non-preemptive priority queue scheduling algorithms will complete all four processes at the same time, but not in the same order. In which algorithm will Process 1 finish first? Provide the time Process 1 finishes and explain your answer.
(ii) If the round robin scheduling algorithm is used, which process will finish first? At what time will it complete? b.
(5 pt) Using a variable-partitioned multiprogramming memory, which of the four holes shown below will be used to satisfy a 40 KB program requirement under the conditions of:
___ Best-fit ___ Worst-fit
9. (2 pt each) Circle or highlight the correct answer to the following questions / statements about data communications:
(a) What characteristic of an analog signal is measured in Hertz, or cycles per second? a. Amplitude c. Phase b. Frequency d. Skew
(b) What measurement unit describes the speed and capacity of a communication channel? a. Throughput c. Response Time b. Access Time d. Data Transfer Rate
(c) ____ can be produced by a variety of sources, including electric motors, radio equipment, and nearby power transmission or communication lines. a. EMI c. Distortion b. Attenuation d. Signal/noise (S/N) ratio
(d) A(n) ____ can extend the range of an electrical signal by boosting signal power to overcome attenuation. a. repeater c. amplifier b. return wire d. signal wire
(e) Which of the following does not allow multiple messages to be carried on a single channel? a. time division multiplexing c. packet switching b. frequency division multiplexing d. half-duplex