Overview of URN

  • Daniel Amyot, U. of Ottawa DanielAmyot

  • ITU-T (Telecom) standardization process

Principles

  • User vs. Systems requirements

  • Several notations:

    • GRL (Goal-oriented Requirement Language)

    • UCMs (Use Case Maps)

  • Graphical syntax

Capabilities

  • Capture user requirements

  • Scenarios as 1st class entities

  • Focus on elicitation and transition to design

  • Allocation of scenario responsibilities to components

  • Detection/reasoning of features

  • Address goals and NF requirements

  • Formal grammar (supports transformations and exchanges)

GRL

Example of GRL model (source here)

grl

A goal is an objective or concerned used to discover and evaluate requirements.

Basic concepts

Goals

business or system

Alternative means

of achieving goals

Rationales

for contributions and decisions

Basic notation

GRL Notation (source here)

grl annoted

  1. Softgoals (fuzzy goals)

  2. Contribution link

  3. AND composition

  4. Impacts

  5. Correlation

  6. Belief

More here.

Impacts

  • positive/negative and sufficient (make/break)

  • positive/negative but insufficient (help/hurt)

  • unkknown positive/negative (some+/some-)

Benefits

Evaluation of candidate solutions (source here)

grl solutions

  • Different level of abstractions

  • Tool supported

  • Trade-off analysis

Use Case Maps

UCMs Notation (source here)

ucm

A functional requirements is a requirement defining functions of the system.

Capabilities

  • UC capturing and elicitation

  • UC validation

  • High-level architectural design

  • Test case generation

Basic concepts

Scenario

a partial description of system usage

Responsibilities

scenario activities (something to be performed)

Component

entity (software or not) that performs a responsibility

UCMs Notation (source here)

ucm

Basic notation

More here.

  1. Start point

  2. Pre-condition

  3. Triggering event

  4. Casual paths

  5. Responsibilities

  6. Fork

  7. Condition

  8. Endpoint

Benefits

  • UCMs can integrate many scenarios

  • To analyze potentially conflicting scenarios

  • To generate artifacts (MSCs, SD, test cases)

  • To analyze alternatives designs

Alternative component structures (source here)

ucm structures

Mapping with the Unified Framework

The 7 kinds of class

  • Requirements

    • Concrete Environment

    • Abstract Environment

    • Scenario

  • Design and implementation

    • Architecture

    • Implementation

  • Goals and project

    • Goal

    • Project

References between classes

refBetweenClasses
Figure 1. References between classes (source here)

Applied to URN

Kind of class URN Concept Details

Concrete Environment

Actor, Resource

Abstract Environment

Actor Boundary, Belief?

Scenario

UCM Paths

Architecture

Out of scope

Implementation

Out of scope

Goal

Goal, Softgoal, Belief?

Project

Task, Resource?

Appendix A: Appendices

GRL Notation

grl notation
Figure 2. GRL Notation (source here)

UCMs Notation

ucm notation
Figure 3. UCM Notation (source here)

Appendix B: Useful links