SE 380 Software Architecture

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SE 380Software Architecture

• Case Study JCI Comfort Chart

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Overview

• JCI Metasys Extended Architecture

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Comfort Chart Application

• Port existing application to new platform

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ABC

• Stakeholders
• JCI, JCIs clients, Developers (MSOE)
• Technical Environment
• Must use .NET technology
• Thin client no special installs or downloads
• Assume IE 6.0 at client
• Must use JCI supplied MSSDA dll to access system
• Architects Experience
• Limited knowledge of .NET technologies

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ABC - Requirements

• Requirements (Quality Attributes)
• Performance
• lt30 seconds to first launch
• lt10 seconds subsequent launches
• Usability
• Provide similar user experience to current
  application (stand alone Windows app)
• Modifiability
• Provide framework for future visualization
  applications
• Interoperability
• Thin client IE 6.0 web browser

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Tactics

• Performance
• Three-tier architecture
• Limit processing at client
• No large download for client (render at server)
• Caching at middle tier
• Limit redundant network traffic
• Modifiability
• Layered architecture with well defined interfaces
• Semantic coherence
• Interoperability
• Due all processing at server and deliver generic
  HTML to client
• Usability
• Conflict could not achieve
• HTML is not able to deliver rich user experience
  without numerous add-ins (JavaScript, DHTML, etc.)

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Handling a Conflict

• Serious clash of requirements
• Performance/Interop (thin client) vs. usability
• Lack of technical knowledge
• Needed to prototype

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A Prototype Physical View
Clients
Server
App User (Iexplorer)
NAE
ADS running Comfort Chart
NAE
App User (Iexplorer)
NAE
App User (Iexplorer)
App User (Iexplorer)
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Layered View
Client
MetaViz Comfort Chart GUI
MetaViz Comfort Chart App. Logic
ADS Server
MetaViz Blackboard
MetaViz Reusable API
MSSDA dll
NAE/Site Director
Basic Web Services
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Prototype Results

• Simply could not deliver rich user experience.
• What now?
• Back to drawing board.

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Requirements Pass 2

• Requirements (Quality Attributes)
• Performance
• lt30 seconds to first launch
• lt10 seconds subsequent launches
• Usability
• Provide similar user experience to current
  application (stand alone Windows app)
• Modifiability
• Provide framework for future visualization
  applications
• Interoperability
• Thin client any web browser
• ADD Requirement IE 6.0, .NET 1.1 installed

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Architecture Pass 2

• Architecture is essentially unchanged
• Deliver a Windows Forms user control instead of
  HTML
• User experience similar to any Windows app
• .NET includes intelligent caching that should
  meet performance requirements
• Multiple deployment options not available with
  HTML solution