Software Architectures - Second Semester 2013-14 : Comprehensive Exam (EC- 3 Regular)

Birla Institute of Technology & Science, Pilani

Work-Integrated Learning Programmes Division

Second  Semester 2013-2014

Comprehensive Examination

(EC-3 Regular)

Course No.                    : SS ZG653 

Course Title                  : SOFTWARE ARCHITECTURES  

Nature of Exam            : Open Book

Weightage                     : 50%

Duration                        : 3 Hours 

Date of Exam                : 05/04/2014      (FN) 



Q.1. Differentiate between
(a) Interactive Systems and Adaptable Systems 

                                                                                                                                   [5]
(b) MVC Pattern and PAC Pattern 

                                                                                                                                   [5]


Q.2. Write a short note on
       (a) Documenting Architecture with a focus on Views. 

                                                                                                                                   [5]
       (b) Microkernel Pattern with a specific focus on adaptability to evolving hardware and software.

                                                                                                                                   [5]

Q.3   (a) Security is a one of the most important quality attribute. Take an example of a remote proxy that performs the function of protection and firewall, to explain the implementation of security tactics. List suitable examples. 

                                                                                                                                    [5]

Q.3 (b) For the same proxy take an example of a client accessing the external data (over the network) (Hint: Use of proxy pattern). For the scenarios (i) Connect with original to get the latest data when the data in proxy is stale (ii) Provide the data to the client from the proxy as the data in the proxy is not stale, draw only an Message Sequence Charts to depict the scenarios. 

                                                                                                                                    [5]

Q.4. Case Study: Lift car and Lift Control System

A single lift control system (LCS) controls more than one lifts. This control system consists of all of algorithms to control the electrical input to control and manage the movement of lift cars (LC). A communication bus is used to send in commands and receive data from the lift car.

Every lift car can carry varying number of passengers i.e. laden weight of the lift may vary across different models. Each car does have its maximum speed which can be reached or allowed Example: A service lift is a slow speed lift whereas passenger lifts are higher speed when compared to service lift. Lift car has a user interface which shows the present floor, present weight of the lift, speed of the lift and shows time-of-day. An input interface is present which allows certain inputs from the users for floor request, alarm and internal light switch on/off. An emergency light is installed which switches on when the power fails. This light is controlled by the lift control system.

An auto rescue device may be installed on the lift. This is configured in the LCS as well as lift car. This is a mechanical device which gets the LC to the nearest floor in case of power failure and also can detect as to which floor the lift is at. Thus makes it easier to reset the position which otherwise will have the lift to be brought to the lowest floor to reset the position in case of power failure.

An LCS has control algorithms to control the speed, soft start and stop of the lifts and has all the data pertaining to the movement, speed, position and other status of the LC. This is displayed on the Graphical User Interface of the LCS. A keyboard can be connected to the system to configure and control the system.

Questions:

(a) Create required class diagrams/Block diagram so as to demonstrate that the functionalities so depicted covers all requirements 

                                                                                                                                [10]
(b) Create Message Sequence Diagrams for the following scenarios  :
                   -  Power failure scenario for LCS  

                                                                                                                                  [5]
                   -  Power failure scenario for LC 

                                                                                                                                  [5]

**********