13 Architectural Design

7/31/2019 13 Architectural Design

http://slidepdf.com/reader/full/13-architectural-design 1/19

Architectural Design

Lecture-7

1Software Engineering



Overview

Announcements, Review

Creating an Architectural Design




Announcements, Review

DD-1 assignment

- (due next week before labs)

Design patterns

- lab tasks




Review

Software Design- Translating Analysis model into Design model

- Characteristics of Good Design

- Measuring Design Quality (FTR, FURPS)

- Design Concepts (abstraction, patterns, modularity, etc.)

- Design Model




Architectural Design

What is it?

Who does it?

Why is it important?




Software Architecture

Software architecture must model the structure of asystem and the manner in which data and proceduralcomponents collaborate with one another.

Benefits?

Software components (OO class to DB)

Architectural Model (Gestalt view)

“The architecture of a system is a comprehensive framework that describes its form and structure – its

components and how they fit together .”

Jerrold Grochow




Data Design

Architectural level- Files and databases

- Data mining techniques (KDD)

- Data warehouses

Component level-

Data structures- Data design principles




What principles are applicable to

data design?

1. Systematic analysis

2. All data structures and operations should beidentified

3. Stepwise refinement

4. Limited access/knowledge of data structure

5. Library

6. Software design and PL support for abstractdata types




Architectural Styles and Patterns

Style- Transformation imposed on the design of an entire system

- To establish a structure for all components of the system

- Sets of components and connectors, and constraints

Pattern- Scope is less broad (one aspect of architecture)

-

Describes how software will handle some aspect of its functionalityat the infrastructure level (e.g. concurrency)

- Address specific behavioral issues (e.g. how a real-time applicationhandles synchronization or interrupts)




Architectural Styles




Architectural Styles (cont)

Data-centered architecture

Data-flow

Call and return

Object-oriented

Layered




Architectural Patterns

A software architecture may have a numberof architectural patterns that address issuessuch as

- Concurrency (OS, task scheduler),

- Persistence (DBMS, app level),

- And distribution (broker pattern, e.g. CORBA).




Organization and Refinement

Define a set of design criteria

How to assess an architectural style?

Control- How is it managed?

- Any control hierarchy?

- Role of components?

Data- How is it communicated between components?

- Flow is continuous or sporadic?

- Mode of data transfer?




Architectural Context

Represents how the software interacts withentities external to its boundaries

- Superordinate systems

- Subordinate

- Peer-level

- actors




Architectural Context Diagram




In-class Exercise

Draw an ACD for your team project.

Software Engineering 17



Refining the Architecture into

Components Begins with the classes from analysis model

If a conventional (non-OO) approach is chosen,can be derived from data flow model

Infrastructure domain (e.g. memory mgnt,communication, db, and task mgnt components)

“The structure of a software system provides the ecology in which

code is born, matures, and dies. A well-designed habitat allows for

the successful evolution of all the components in a software

system.”

R. Pattis




Software Tools

Architectural Design tools model the overallsoftware structure by representingcomponent interfaces, dependencies and

relationships, and interactions.

- Adalon (www.synthis.com) – for Web-based components

- ObjectiF (www.microtool.com) – UML-based design tool for

component-based architectures (e.g. Coldfusion, J2EE, Fusebox)

- Rational Rose (www.rational.com)


http://www.synthis.com/

http://www.microtool.com/

http://www.rational.com/

http://www.rational.com/

http://www.microtool.com/

http://www.synthis.com/

13 Architectural Design

Documents

Transcript of 13 Architectural Design