Comp150CPA: Clouds and Power-Aware Computing
Quiz 2 Review Answers
group member 1: ____________________________ login: ______________
group member 2: ____________________________ login: ______________
group member 3: ____________________________ login: ______________
group member 4: ____________________________ login: ______________
group member 5: ____________________________ login: ______________
My quizzes concentrate upon broad understanding
and in-class exercises. Problems will be similar to those on the
exercises. My quizzes -- by definition -- concentrate on "what things
mean" and not on broader impacts; you will not see a
so-called "advanced" question on the quiz! I will be emphasizing the
following issues from lectures dated 03/09/2011 and beyond:
- Designing the cloud.
- Business Process Description: BPEL and BPMN.
- Orchestration and Choreography: WS-CDL.
- Event-Condition-Action modeling.
Here are some sample questions of the kind I am planning:
Please fill in the blanks: in designing a service,
one must remember that Map/Reduce is not designed for
____interactive____ use, and that one must typically
store the results of a M/R query in a ____distributed datastore/hash table____
instead. In employing a distributed hash table in a cloud
application, one must remember that it is typically difficult
to employ ____Map/Reduce____ in a DHT. Thus a major
part of cloud design is to arrange to ____transfer data____ between
the two storage formats.
Please describe what kinds of data needed (in order to program an
application) are not coded into a BPMN diagram.
Answer: It shows the interactions between entities,
but does not document the data format or requirements.
- Please fill in the blanks: the difference between orchestration
and choreography is that
orchestration specifies the ____overall____ sequence
of events, while choreography specifies ____local____
interactions. The true need for choreography arises from the fact
that in BPEL, there is no well-defined notion of a ____subroutine____.
Please fill in the blanks:
an ECA model contains ____events____ that describe
what happened, ____conditions____ that describe the
nature of that, and ____actions____ that describe
what to do in that case.
While programmers see the cloud as easing programming, business
decision-makers see it as a way of reassigning ____risk____
to another party. This is not a perfect solution, however, because
public clouds cannot presently guarantee the ____security/privacy____
that they claim.