Essentials of Design and Design Activities

Review Questions

1. What is the primary objective of systems design?

2. What is the difference between systems analysis and systems design?

3. List the major elements that must be designed for a new software application.

4. List the models that are used for systems analysis.

5. List the models that are used for systems design.

6. What is the difference between user-interface design and system-interface design?

7. On a project that uses iterations to develop the system, in which iteration does systems design begin? Explain why.

8. What is the difference between architectural design and detail design?

9. Designing the security and controls impacts the design of which other elements?

10. Describe what is required for database design.

11. What is a LAN? When would it be used in deploying a new system?

12. What is three-layer design?

13. Describe the contents of each layer in three-layer design.

14. List the different types of client devices in a client/server architecture.

15. What is the difference between HTTPS and HTTP?

16. In the use of software over the Internet, what are the two main security issues that must be considered?

17. Describe the primary factors that affect throughput for Internet systems.

18. List five issues that are important when considering an external hosting company.

19. What is the difference between cloud computing and virtual servers?

20. Why do companies use colocation facilities?

21. Describe the issues to be considered when designing for multiple clients.

22. What is a VPN? Why would a company use a VPN?

Problems and Exercises

1. A financial corporation has desktop applications running in several different offices that are all supported by a centralized application bank of two computers. In addition, there is a centralized database, which requires three servers. Draw a network diagram representing this requirement.

2. A sales organization has an Internet-based customer support system that needs to support every type of client device. The server configuration should be a normal layered application server and database server. Draw a network diagram representing this requirement.

3. A medium-sized engineering firm has three separate engineering offices. In each office, a local LAN supports all the engineers in that office. Due to the requirement for collaboration among the offices, all the computers should be able to view and update the data from any of the three offices. In other words, the data storage server within each LAN should be accessible to all computers, no matter where they are located. Draw a network diagram that will support this configuration.

4. A small start-up company has a Web-based customer sales system that is written by using PHP and JavaScript. The company is deciding whether to host the system on its own servers, contract with a hosting company for a virtual server, or go to Amazon's cloud. Volumes are expected to be low at the beginning, and it is hard to predict a growth pattern, although there is potential for rapid growth. Decide which alternative the company should choose. Defend your decision by giving advantages and disadvantages of each solution based on the characteristics of the start-up company.

5. Describe the differences between HTTPS and a VPN. What kinds of computing and networking situations are better suited to HTTPS? What kind of computing and networking situations are better suited to VPN?

6. Find four separate hosting providers and compare their offerings, including prices. Put your answer in a table showing the results of your research.

7. Compare screen size, resolution, and other important display characteristics of five popular Internet-enabled smart phones. Which would you rate as the best? Defend your answer.

8. Research the issues related to supporting a very large database that must be distributed across multiple servers. Write a list of the issues that need to be addressed and the alternative solutions for a distributed and partitioned database where (a) all servers are colocated in the same data center and (b) the servers are located in separate data centers.

Case Study: County Sheriff Mobile System for Communications (CSMSC)

Your assignment: Recommend a communication and network solution for the county sheriff's department. It can be any combination of Internet, VPN, Wi-Fi , telephone, and satellite communication. The applications can be custom built, with device-specific or HTML-based user interfaces. Although HTML tends to be more versatile, it has drawbacks regarding security; display can also be an issue on devices that don't have browser support.

As always, the budget is tight, so your solution should be as economical as possible. Develop a network diagram that depicts your proposed solution. Also, explain your solution and justify your design.

1. Design the environment for the SBRU information system by drawing a network diagram. Include what might be necessary to support online chatting capabilities.

2. Considering that everything is designed to operate through the Internet with browsers or smart phones, how simple does this architecture appear to be? Can you see why Web and smart phone applications are so appealing?

3. What aspect of design becomes extremely important to protect the integrity of the system?

Running Cases: On the Spot Courier Services

1. Make a list of the equipment that Bill should purchase to support his new system. Include all equipment that will be needed for the home office, the drivers, and at Bill's residence. Identify and describe actual equipment that can be purchased today. Estimate the cost of the equipment.

2. Describe any special software that may be needed. The software engineer is developing the application software (package scheduling and processing, accounting, etc.), but no special software is required for connecting the devices or communications between them.

3. Develop a network diagram showing how all the equipment will be connected. Identify Internet connections, VPNs, and telephony links as appropriate.

Answer these questions in light of HIPPA requirements:

1. Does HIPAA apply to the RTGM system? Why or why not?

2. How should the system ensure data security during transmission between a patient's mobile device(s) and servers?

3. Consider the data storage issues related to a patient's mobile device and the possible ramifications if the device is lost or stolen. What measures should be taken to protect the data against unauthorized access?

4. Consider the issues related to health care professionals accessing server data by using workstations and mobile devices within a health care facility. How will the system meet its duty to record and examine access to ePHI? If a health care professional uses a mobile device outside a health care facility, what protections must be applied to the device and/or any data stored within it or transmitted to it?

5. Consider the issues related to wired and wireless data transmission between servers and workstations within a health care facility. What security duties, if any, apply to transmissions containing ePHI? Does your answer change if the servers are hosted by a third-party provider?