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?