Design of an OnlineVoting System

COMP 204, Spring 2001Adrian Ilie & Miguel A. Otaduy

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

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.

Structure of a Node

election objects user objects managers DB voters DB candidates /

answers DB results DB

Connecting the Nodes (1)Having distributed databases means we have to search for data at different nodes...

Connecting the Nodes (2)… but it’s distributed!

Abstract User Class implements

authentication methods

serves as asuperclass for concrete user types

User Type: VoterCreated at engine with the database that contains the data about it.

User Type: CandidateAll interactions are local.

User Type: ManagerAll interactions are local.

Menus and Actions

Election Class

Handling Election Types

Communication Issues

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.