Design of an Online Voting System

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Design of an OnlineVoting System
COMP 204, Spring 2001
Adrian Ilie Miguel A. Otaduy
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Design Goals

• handle elections of any kind at any
  administrative level
• provide an easy-to-use on-line (web-based)
  interface
• allow both a distributed and a stand-alone system
  organization

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Example of a Distributed Election

• Consider an election day when elections are held
  at the national, state and local level. Voter
  data is retrieved from a census database,
  distributed in three locations.

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Structure of a Node
FAÇADE

• election objects
• user objects
• managers DB
• voters DB
• candidates / answers DB
• results DB

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Connecting the Nodes (1)

• Having distributed databases means we have to
  search for data at different nodes...

CHAIN OF RESPONSIBILITY
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Connecting the Nodes (2)
but its distributed!
PROXY
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Abstract User Class

• implements authentication methods

• serves as a superclass for concrete user types

FACTORY METHOD
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User Type Voter

• Created at engine with the database that
  contains the data about it.

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User Type Candidate
All interactions are local.
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User Type Manager
All interactions are local.
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Menus and Actions
COMPOSITE
FLYWEIGHT
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Election Class
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Handling Election Types
STRATEGY
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Communication Issues
PROXY
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OFF-LINE Application

• Creation of proxy objects for remote engines. The
  local chain is set at each node. Customers have
  to agree on what nodes are included in the global
  system.
• Creation of election objects and the manager
  database.
• Maintenance of voter and candidate databases.