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.