exercises

19. groupware

EXERCISE 19.11

What are the two main architectures used for groupware systems? Identify the strengths and limitations of each and suggest how they can be resolved.

answer available for tutors only

The two main architectures are client-server and replicated.

Client-server: one set of data/programs, no updating problem; but poor feedback, network bottlenecks and problems with server failure.

Replicated: repetition of data/programs therefore version control problems; but much lower network traffic.

Various forms of locking ease both: in client-server the user with the lock can update a local copy which is sent to the server at the end of a transaction, in replicated architectures locks make the peer-peer update algorithms far easier - however, locking reduces the fluidity of cooperation and may reduce the rate feedthrough. Another solution is to take a hybrid approach. The answer should explore which aspects are best handled by which architectural element.

Look at the papers linked from chapter 19 on the textbook's web site www.hcibook.com/e3/chaps/ch19/links/ for more about these issues.

Other exercises in this chapter

ex.19.1 (ans), ex.19.2 (ans), ex.19.3 (tut), ex.19.4 (tut), ex.19.5 (tut), ex.19.6 (tut), ex.19.7 (tut), ex.19.8 (tut), ex.19.9 (tut), ex.19.10 (tut), ex.19.11 (tut), ex.19.12 (tut), ex.19.13 (tut), ex.19.14 (tut), ex.19.15 (tut), ex.19.16 (tut), ex.19.17 (tut), ex.19.18 (tut), ex.19.19 (tut), ex.19.20 (tut)

all exercises for this chapter