Usage Scenario:
Conversation Protocols Portfolio User
Name: Conversation Protocol of student participating in UROP
Author(s):
URL(s) or other references:
References: 1. B. Benatallah, F. Casati, F. Toumani and R. Hamadi, Conceptual
Modeling of Web Service Conversations, In J. Eder and M. Missikoff eds, Advanced
Information Systems Engineering, 15th International Conference (CAiSE'03), Klagenfurt,
Austria, June 16-18, 2003, Springer, pp. 449-467, LNCS 2681;
Domains: using a portfolio to support an undergraduate research program
Description
The UROP program is...
This usage case describes the…
The main purpose of this scenario is to understand and make explicit …
Issues
These scenarios show that…
Actors & Goals
[Use a Sakai persona defined in a separate document. If necessary, create such a
document. Attach to this doc as appendix.]
Actor 1: Sara McCloud, Tenured Professor - DRAFT3
Goals of Actor 1:
Stakeholders & Interests
Interested parties are the bookseller, the customer, and middleware vendors. On the
service provider's (bookseller's) side, a richer protocol language enables the definition
of more sophisticated behavior (in the specific example of a bookseller, this may include
specifying different "penalties" for the cancellation of an order, and different constraints
to denote when an order can be cancelled).
On the client's side, the interest lies in easier understanding of the service's behavior
and in the simplified development, thanks to the additional support that is enabled by
design and runtime tools that are aware of the semantic annotations and of how to
leverage them.
On the middleware vendor's side,
Modification History
Use Case Title:
Bookseller's conversation protocol
Actors/Roles
Same as scenario actors
Goals/Context
search and order books
Assumptions
None
Scenario/Steps
The steps of the conversation protocol of the booksellers are described in [REF1]:
This includes searching for a book, ordering a book, cancelling an order (before the
shipment of the book), shipping a book, returning a book (this is allowed with a period of
time).
We have used an extended state machine model to describe conversation protocols.
Ontologies and Semantic Descriptions
We based our analysis on Web portals (in this case booksellers' portals) rather than web
services because: (i) Web services area is still rather immature, (ii) E-commerce portals
often include ``terms and conditions’’ documents that describe the semantics of many
operations (in particular those that involve some form of commitment on the client or the
provider side). We have used a simple state machine model and we extended it to
represent abstractions such completion (implications and effects of an operation from a
user perspective, e.g. whether user can cancel an operation and what is the cancellation
cost) and activation abstractions (when a transition one state to another must/can
occur).
Completion abstractions include:

Compensation (for example, user can cancel a previously performed operation by
invoking a given compensation operation). Compensation may have an associated
cost and is typically allowed only within a period of time. In the bookseller's example,
these include the following:
1. A buyBook transition can be canceled only within a certain time interval T_max
2. if it is canceled before T_min, there are no penalties
3. if it is canceled after T_min but before T_max, shipping expenses have to be
refunded.

Resource locking (the execution of certain operations seem to acquire some
resources for the client (e.g., hold seats on a plane)). Again this may come with a
cost and may have a validity limited in time. In the bookseller's example, a used copy
of a book can be reserved (locked), but only for a certain period of time. After this
period, the lock expires. In a variation of the scenario, one can think that the "locking"
is only available to certain customers ("gold" customers), or at a cost.
Activation abstractions:
These include implicit and timed transactions. There are cases in which transitions
between states occur without an explicit invocation of operations. Some of these
transitions are timed in the sense that they occur automatically, e.g., after a time interval
is elapsed.
For both activation and completion abstractions, the issue is how to semantically
characterize the definition of each state transition in the protocol. The characterization
may be horizontal or vertical. Horizontal semantic annotations are not specific to any
vertical domain, but are instead generally applicable to characterize the behavior of
many different services. The examples provided above are horizontal, as they deal
generically with "cancellation", "time", and "cost".
Other semantic abstractions/annotations can be vertical. For example, the bookseller
can state in the protocol definition that the effect of a certain state transition (triggered
by an operation invocation) consists in activating a subscription to a journal.
Reasoning Techniques Required

Compatibility between services

Validation of service composition models (e.g., checking the correctness of a
composite service with respect to the usage of component services)

Joint analysis of composition and conversation models
Appendix 1: Personas
Sara McCloud, Tenured
Professor - DRAFT
“Publish or Perish”
Sara has been with UC, Berkeley for the past
15 years after a 5 year stint as an instructor
at a community college back east in her
home town. Even though it seems she is
working 24/7, she loves her job. When she
is not preparing for, administering and
teaching in the classroom, she spends as
much time as possible on her research. She co-authored the book, “A Human
Perspective on Microbiology” and is currently working on the 2nd edition. Besides her
teaching and research, Sara is involved in several campus-wide initiatives that also take
up quite a bit of her time off and on.
Sara has been teaching the undergrad “General Biology” (aka Biology 1A) course for
several years. She updates her curriculum a bit each semester but for the most part,
she feels she has got a sound syllabus and related course content that she is able to
leverage from semester to semester. Sara has been using Blackboard to supplement
the classroom since it was introduced on campus several years ago. She uses her
course site to communicate with students and share course content like reading
materials and assignments. She worked with her TAs when they adopted Blackboard to
create the structure of her site and it has not changed much through years. Although
with each new group of TAs there are always suggestions for ways to improve things.
For instance, she used to group course resources in folders by type of work like
“homework”, “readings”, “other resources”, etc. Last semester, they created a folder for
each class session and put all resources for that session in a folder. Students seemed
to be able to find materials easier with the new organization but the jury is still out. Sara
typically assigns 1 or 2 TAs as leads. A large part of their responsibility is to maintain
the course site.
“General Biology” is a large class. Sara lectures each week and she has several TAs
that facilitate the approximately dozen each discussion and lab sections. Students are
required to sign up for the lecture along with a lab and discussion. Keeping all this
straight can be challenging, especially in the beginning of the semester when students
are switching between sections often as they coordinate their schedules. Since
Berkeley’s registrar system only cares about student’s course membership for the
lecture (primary section) for grading purposes, they quit keeping track of student’s
sections after the first few weeks of the semester. At that point, the teaching team must
keep track of lab and discussion section membership.
Once TAs are assigned to her sections, Sara has to make sure they have access to the
class site. She does this manually since the campus systems do not keep track of it. A
TA may be responsible for one to several sections. Although most communication and
content is shared across sections, there are times her TAs need to work with their
specific sections which is not easy in Blackboard. It gets even more cumbersome with
the few students that are not taking all 3 sections in one semester. Since all students
use the same site, material pertaining to the section type they are not involved in
becomes extraneous information. Sara is aware that students are busy and have a lot to
keep track of. She wants them to be able to easily find and use course material.
Sara is both nervous and hopeful about the campus shift to bSpace. She is comfortable
with Blackboard but hopes that bSpace will automate and streamline managing course
and section membership for her, her TAs and students.
Goals:
•Leverage previous semester course materials
•Not to have to ask for help
•Spend as much time as possible focusing on her research -- spend as little time as
possible doing administrative work; she’ll delegate to her TA’s
•Distribute course materials efficiently
•Communicate more efficiently with students and TA’s (focused communication to
relevant recipients)
Remy Feingold,
Instructional
Designer/Tier 2
Support
“Education Technology
Innovator”
Remy works at a medium-sized
university where him has been
given the charge to enable
faculty to effectively use
technology in their teaching.
Being a technology aficionado
and having been a high school teacher in a former life, his job as an instructional
designer suits his well. Him loves it when an instructor calls his a “life saver” because
him was able to solve a complicated technology problem or him is able to figure out a
new way of using technology in the classroom. Though dedicated to his job and willing to
put in extra hours when warranted, Remy does have a life outside of work. He does not
want problems that come up in his job to eat into time him would rather spend with his
wife or dog.
While his department does have one help desk staff to take care of typical questions that
faculty might have, one of the responsibilities Remy has is dealing with the more
complicated issues that come in the use the university’s course management system.
Issues like moving content from one system to another, trying to combine different
courses into one site, and dealing with the multitude of methods that departments have
for enrollment in courses are just a flavor of the types of problems Remy might
encounter on any given day.
Because the CMS is only one system that Remy supports, him wants large
scale/repetitive tasks like transferring content to be done by the system rather than
having to do all the work manually. Also, him wants the system to be very flexible for
dealing with the “one-offs” that faculty seem to so adept in producing. Rather than
finding work-a-rounds, Remy prefers that the system allow him to configure things rather
than how they might have typically been presented to faculty.
Goals:




Enable faculty to use technology effectively
Spend less time doing mundane tasks, more time on creative problemsolving
Work hard, but have a balanced lifestyle
Be known as an education technology expert