Assignment

1. Consider the design of a calculator application, such as the Windows Calculator.

Part 1) How might you design this application (i.e., design "in the large"), and describe why you made the choices you did.
Part 2) What would be a design "in the large" to avoid for this application, and why?

2. Examine Final.py.

The input() function is well known to be a security vulnerability because the input is evaluated by python.

Part 1) Run Final.py three times with three separate inputs: your name in quotes, 5+9 in quotes, 5+9 without quotes. Write down or capture the resulting outputs. Explain what is happening, and why it is convenient (in this case).

Part 2) Run Final.py with the input __import__("os").listdir('.'). Although this particular input string is harmless, use this example to explain why the input() function is dangerous?

Part 3) As a software systems engineer (not the software engineer/developer writing the code), what would you do to avoid these types of security vulnerabilities?

3. Consider the following scenario. You have recently delivered the first phase of a mission-critical software intensive system. All of your customers and stakeholders are very happy, and you proceed with the second phase of development. This phase will add another set of highly desired features and will take about a year to develop and deliver. You are doing incremental development, so multiple internal versions will be built and tested prior to delivery. You currently use a configuration management system, with all development organized in the trunk. You have a release plan which generally specifies the iteration in which the second phase features will be developed. All is going according to plan.

About two months into the second phase, you get a call from your user point of contact. They have an urgent problem with the system and need you to address it. You have additional resources (developers, testers, equipment, etc) available to address the problem. However, it will require simultaneous development on the same system, with one team working on the fix and the other on the second phase.

Part 1) Explain how you would adapt the software process to simultaneously address the fix and continue work on the second phase features

Part 2) Would you make any changes to your configuration management strategy to accommodate the fix? Why or why not?

Part 3) How would you structure testing of the fix prior to delivery?

Part 4) Would you consider including any features of Phase 2 in the "fix" delivery? What factors would drive your decision?

Attachment:- Code.rar