cots acquisition cots acquisition impact analysis lianne versluis
TRANSCRIPT
COTS Acquisition Impact Analysis
Lianne Versluis
Overview of the topic
• COTS Acquisition Impact Analysis• Proposed by Mark Feblowitz and Sol
Greenspan, 1998• Analyzes the impacts of the
acquisition of a COTS product
What is COTS?
• COTS stands for Commercial Off-the-Shelf
• Also called package systems or off-the-shelf components
• Term originates from the requirements engineering field
COTS: a definitionSoftware that is:1. sold, leased, or licensed to the general
public, 2. offered by a vendor trying to profit from
it, 3. supported and evolved by the vendor,
who retains the intellectual property rights,
4. available in multiple, identical copies5. used without source code modification.
COTS product characteristics
• it exists à priori• it is available to general public• it is sold, leased or licensed
Benefits & DrawbacksBenefits:• reduced time-to-
market• Money-saving by
not building in-house
• competition between vendors turns always to the customer profit.
Drawbacks:• non-control over
updates and maintenance
• risk of dependence on a vendor
• difficult integration
Phases of Impact Analysis
Other selection methods
Several other selection evaluation methods exist: for example, the PORE, OTSO, CAP, and STACE methods
Positioning• Criteria-based: OTSO and STACE• Scenario-based: Impact Analysis• Goal-oriented: Alves & Finkelstein• Metrics-oriented: CAP• Mixed: PORE
PDD
Example: baseline scenarioTitle Citizen returns the borrowed booksGoal Obtain the borrowed booksContext Citizen has a Library CardParticipants
LibrarianCitizen
Resources BooksLibrary CardLibrary Database
Narrative 1. Citizen calls in (with the borrowed books) at the Librarian2. Librarian asks for Library Card3. Citizen gives Library Card4. Librarian checks Library Card 5. Librarian gives back Library Card6. Librarian obtains the borrowed books
COTS scenarioTitle Citizen returns the borrowed booksGoal Obtain the borrowed booksContext Citizen has a Library CardParticipants
CitizenLibrarian
Resources
BooksLibrary CardLibrary DatabaseLibrary System
Narrative 1. Citizen calls in (with the borrowed books) at the Library System2. Citizen scans his/her Library Card 3. Citizen returns the books
Modified responsibilitie
s
Added resource
Three steps instead of 6
Template
COTS Candidate: Candidate X Impact Type Resource
impactParticipants impact
Information flow impact
Responsibility impact
Is there an impact?
Y/N Y/N Y/N Y/N
Removed or added?
Removed/Added
Removed/Added
Removed/Added
Removed/Added
Gravity 1 to 5 1 to 5 1 to 5 1 to 5Remarks:
Choose COTS Candidate: Y/N
Questions?