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1、east china jiaotong university (ecjtu)subject : software architecture assignmentdeadline: 12th week total score: 40 following are the list of questions for your assignment. in order to answer these questions, you are allowed to search the information from internet and books. note: the assignment sho

2、uld be done in a group of two students. do not plagiarize (copy) the work. each group assignment should be unique. write down your names, id, course title in the front page. the answers should not be too short. otherwise you will get less score. the assignment should be done professionally i.e. use

3、microsoft word to document the answers, and then print it out in a4 size paper. - name class id class id date：2014.5.10 question # 1: explain the concept of cohesion and coupling in software architecture and design. please explain it with examples and diagrams. (5) answer #1: cohesioncouplingconcept

4、cohesion from a functional point of view to measure the contact module, which describes the function within the module links.the coupling is between the various modules of the software structure of mutually connected a measure, the coupling strength depends on the complexity of the interface between

5、 modules, into, or to access a module point and the data through the interface. classification(1)accidental cohesion. (2)logical cohesion. (3)within the poly (4)within a process polyethylene (5)communication poly (6)in order within the poly (7)function cohesive (1) content coupled (2)common coupling

6、 (3)the external coupling (4) control coupling (5) marker coupling (6) data coupling (7) a non-direct coupling question # 2: which architecture style is best suited for distributed software system? explain it with examples and diagrams. (5) answer #2: from my perspective, client-server architecture

7、is best suited for distributed software system . the principal advantage of this model is that servers can be distributed across a network .a network architecture in which each computer or process on the network is either a client or a server. the system designed by client-server architecture, even

8、if different regions, but also can be distributed in different parts of the client through the communication networks such as the network access server such as database server, so that solved first need to solve the problems of distributed systems. for example, many clients are separated throughout

9、the country, but every client can via the internet access server. in this way, every client can get the information it needs and modify the data which can maintaining data synchronization at the same time. question # 3: explain why design conflicts might arise when designing an architecture for whic

10、h both availability and security requirements are the most important non-functional requirements. (5) answer #3: i think the reason can be attributed to the following three points: a. first of all,non-functional requirements is such a demand,it does not necessarily solve the “i want my system to rea

11、lize the function”,but “how to make this system can run in real environment”.so we can not be divorced from the actual environment. b. in addition,if a system is not reliable operation(for example,at load time,or in the event of a system failure,and so on),it cant meet the needs of customers.assume

12、that the attacker on the outside. how to know the system user is who they say they are, and give them access to authorized functions? how do i protect my system not to attack? considering the network attack, attack launched from inside the machine, or even your own attack. c. in many cases, no singl

13、e architecture style can meet all quality attributes simultaneously. quality attributes are rarely orthogonal a) they interact, affect each other b) highly secure system may be difficult to integrate c) highly available application may trade-off lower performance for greater availability d) high per

14、formance application may be tied to a given platform, and hence not be easily portable e) using large components improves performance and using small, fine-grain components improves maintainability. question # 4: explain the difference between component-based architecture and service-oriented archit

15、ecture (soa)? (5) answer #4: an exact differentiation between service oriented architecture and component based architecture is hard to make, because opinions on what “soa ” exactly is and how it will develop differ. if soa is seen as a new type of architecture that defines the how-to of assigning i

16、nterfaces in a servicing way so that these services can be used in a context free way, it doesn t differ significantly from existing component based framewor ks like enterprise javabeans. if the definition of soa includes the usage of technologies like wsdl, uddi, and soap (and its potential success

17、ors), soa differs in several ways from the “old ” component based architecture. with these technologies software can be built in a completely new way. software developers can use foreign, external “components ” in the form of web services. web services can be used in contexts that werent considered

18、at the time they were built. but soa is not the solution to all problems linked with software development. there are a lot of problems: ranging from finding the required services, providing acceptable performance, security, realising transactions up to maintaining ones own service, even if foreign,

19、integrated services have changed or are closed. there are a lot of problems to resolve, but there are a lot of possibilities too. it will depend on sun or other larger companies, to develop an overall solution, containing solutions to all of these problems. question#5: why is it important that compo

20、nents should be based on a standard component model ? (5) answer #5: because standard component model defines the types of building block, and the recipe for putting them together.more precisely, a component model defines standards for: properties individual components must satisfy methods and mecha

21、nisms for composing components. consequently, a component has to conform to some component model. question # 6 : do you think agile architecture works well ?. briefly motivate your answer in the case you chooses yes or no (5) answer #6: yes , i think agile architecture works well. because agile arch

22、itecture work is: works at a sustainable pace makes good use of motivated individuals embraces pairs and peers respects self-organizing or existing team structures works by influence, not authority knows his stakeholders and the business ensures everyone understands delivers regularly and frequently

23、question # 7: how siemens four view model is different from kruchten 4+1 view model ?. (5) answer #7: kruchten “4+1” view model:from 5 different angles of view, process view, including logical to physical view, development view, the scene view to describe the software architecture. one side of each

24、view only cares about the system, 5 tries to reflect all the software architecture of the system in order to. the following diagram: logical view: when using the object oriented design method, the logical view is the object model process view: describes the design of the system concurrency and synch

25、ronization physical view: describes the mapping relationship between hardware and software to design system, reflected in the distribution of the development view: describes the static organization software development environment what more,kruchten “4+1” view model has a scenarios.scenarios is a vi

26、ew that siemens four view model hasnt.a group of important scene four view by less (morecommon is the case) to work together seamlessly, our scene description the corresponding script (interaction sequence between objects and processes). question # 8: how reusability in product line architecture is different from ordinary reusability? explain. (5) answer #8: ordinary reusability includes software reuse and component reuse. software reuse is the process of imple