Realtime%20Commercial%20Bidding%20System

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Realtime Commercial Bidding System

• Team 6
• Brenda HarveyJohn JohnstonJason
  LaBumbardPeter Tirrell

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Realtime Commercial Bidding System

• Provides realtime bidding capabilities
• Motivation for project
• Strong market demand for e-commerce systems
• Few existing B-2-B commodities brokerages
• Low market pricing means automation needed
• System fills a market niche and does so cost
  effectively

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Overview of Features

• Standard and reverse auctions
• Realtime bidding and viewing
• Self-serve auction setup
• Administrator
• Distributed auctioneer attributes operations
• Account management functions
• Combined account functionality

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Overview of Features continued

• Users may participate in multiple auctions
• Forgotten password retrieval
• On the fly account setup

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Prototype

• Login screen
• Existing and new users
• Auction list view/select
• Join, bid in, and view an auction
• Bid history, withdrawing
• Client-side view of reverse auction

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Login Screen
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Auction Information Screen
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Regular Auction Screen
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Regular Auction Screen 2
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Regular Auction Finished
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Withdrawing a Bid
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Auction Information Screen 2
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Reverse Auction Screen
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Reverse Auction Finished
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Create Auction Screen
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Grey Areas

• What is an Auctioneer?
• Automated piece of code
• One approach handle as distinct class
• Second approach divide functionality to other
  classes

• Why an Administrator?
• Can all site maintenance be automated?
• What can be handled by auctioneer or user
  account functions and what cannot?

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How Problems Were Solved

• Auctioneer
• Logically divide auctioneer data and
  functionsinto auction and user account classes
• Avoid redundancy and simplify design
• Site Administration
• Create an administrator class
• Administrator basically a special type of user
  account

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Description of Class Model

• Aggregated under Realtime Auction Site
• Makes use of Administrator
• Abstract classesAuction
• User account aggregated for client and bidders
• Client side login, sign-up, get password
• Auctioneer attributes and functionality
  distributed among several classes

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Class Model
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Sequence Diagrams

• Generalized overall sequence diagram
• Many possible object interactions
• Not a single stepwise progression of events
• Most possible interactions presented
• Use specific sequence diagrams
• Depict major interaction scenarios
• Single stepwise progression of events
• Ack used to denote acknowledgement of messages

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Sequence Diagram
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Bidding in a Standard Auction
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Bidding in a Reverse Auction
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Setting up a Reverse Auction
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Setting up a Standard Auction
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Use Case Diagrams

• Generalized use case diagram
• Many possible actor/activity interactions
• Actors include bidder, client, and administrator
• Specific use case diagrams
• Client interactions w/ in progress auctions
• Setting up an auction
• Bidder auction participation scenarios

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Main Use Case Diagram
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Seller Use Case Diagram
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Bidder Use Case Diagram
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State Diagrams

• Used to show possible states of major objects
• Administrator state diagram
• Fail-safe site intervention capabilities
• Auction state diagram
• Describes progression of auction behavior
• User state diagram
• Describes user interaction in realtime
• User account state diagram
• On the fly account maintenance

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Administrator State Diagram
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Auction State Diagram
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User State Diagram
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User Account State Diagram
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Critical System Properties

• Summary of critical system properties
• No distinct auctioneer class
• Administrator
• One user account, both client and bidder
  capabilities
• Self-serve account maintenance
• Auction abstract class and inheritance
• Client-side functionality

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Promela and XSpin

• Analysis of two client-supplied state diagrams
• Performed initial visual analysis of diagrams
• Coded state machines in promela
• Developed basic test case scenarios
• Future work
• LTL
• Additional scenario analyses

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Client State Diagram

• Spin Analysis
• Issue of end_auction signal in any state other
  than Idle results in deadlock
• Failure of auctioneer to send bidok results in
  deadlock in User_Bid state
• Dropped bids on timeout
• Non-Spin Analysis
• No bid-not-ok signal (timeout?)
• What happens when client bid is not high bid?