REALTOR DEMO

Debbie Chyi

November 6, 1998

What is it?

The Realtor Demo is a program that presents a real-world application that relies on and is enhanced by mobile agent technology. This application utilizes mobile agents to handle the information gathering and transaction processes involved in purchasing a home. The program allows the user to query the database of several realtors. A "salesman" agent works on behalf of the user by sending agents that query the databases, then return with thumbnails of those houses which fit the criteria. From the thumbnails, the user can decide on a house he/she wishes to purchase, and the salesman sends an agent to purchase the house from the realtor. The purchase involves a bank agent and an arbiter agent who together ensure that the transaction is properly carried out. When the transaction is completed, the agent returns from the realtor and the full picture of the user's new house is displayed.

The demo assumes that the user has enough cash to pay for the house and the house purchased is actually only a picture of the house--not the house itself. The realtor is also able to sell the same house multiple times. These scenarios may be unrealistic, in the context of purchasing a home, but they fit well with the sale of other items (such as images, sounds, software, etc), and in any case the agent infrastructure is similar.

The program is integrated with a tracker that is especially useful in visualizing the agents at work "behind the scenes." The tracker keeps track of the various agents that are created throughout the program and provides a "map view," which allows the user to see the current position of each agent and the interactions among them.

Note: This demo is only one version of a larger catagory of "salesman demos" that can be used to sell various products from various types of vendors. Many of the terms used in this demo (i.e. "product", "order", "vendor", etc.) are therefore broad terms that can be applied to any of the salesman demos.

The Agents

There are eight types of agents involved in this demo. Some are stationary and some are mobile; some have one instance and some have multiple instances. Each is described below and most agent icons provide a link to the agent's code.

Starter:

• Stationary
• Creates the Bank, Arbiter, Wallet Manager, and Vendors
• Note that in a real-world scenario, a special agent starter would not be needed since each agent would be started by its own establishment

Bank:

• Stationary
• Manages the currency supply
• Distributes money to the user and each of the realtors
• Distributes money in $100 bills and associates a random number with each bill
• During transaction, verifies that money spent is not counterfeit by making sure the random numbers of the bills spent match that of bills originally distributed and do not match that of bills already spent
• If the bank concludes that the money is not valid, the realtor will not sell
• If the bank concludes that the money is valid, it records the random numbers of the bills as being spent and then assigns a new random number to each bill so that the realtor can now safely use its acquired money

Arbiter:

• Stationary
• Acts as a neutral third-party in the transaction between realtor and salesman
• Receives money from both salesman and realtor before actual transaction occurs
• If, after the transaction, either the salesman or realtor complain, holds money received until dispute can be resolved at a later time
• Returns money to salesman and realtor if both parties are satisfied after the transaction

Wallet Manager:

• Stationary
• Holds user's current supply of electronic money
• Gives money to salesman at start of demo

Vendor 1:

• Stationary
• Lyme Realtor
• Maintains a database containing houses which it is marketing

Vendor 2:

• Stationary
• Haverhill Realtor
• Maintains a database containing houses which it is marketing

Vendor 3:

• Stationary
• Piermont Realtor
• Maintains a database containing houses which it is marketing

Vendor 4:

• Stationary
• Grantham Realtor
• Maintains a database containing houses which it is marketing

Salesman:

• Stationary
• Carries out user's requests by sending out either a gathering agent or purchasing agent

Salesman gatherers:

• Mobile
• Query realtor databases and returns with thumbnails of houses that fit criteria
• Multiple may exist in one demo run

Salesman purchaser:

• Mobile
• Purchases desired house from realtor by interacting with arbiter

Action!

Sample run of demo:

• Agent Starter starts bank, arbiter, 4 vendors, and wallet manager
• Each agent will be created and then will jump to its designated machine

• Tracker automatically tracks the agents started
• The tracker can provide a map view that shows the path of each agent and its current position

Tracker Picture

Map Picture 1

• Start Demo
• Salesman automatically obtains the money from the Wallet-Manager

• By clicking "Update Catalog" and sending a default gather, user can obtain a catalog of all houses on the market
• Salesman sends a separate gathering agent to each of the realtors
• Each of the gathering agents jumps to the realtor's machine, queries for all the houses in the realtor's database, and jumps back to user's machine with all the thumbnails of the realtor it queried

Demo Picture 1

Catalog Picture 1

Demo Picture 2

Map Picture 2

• When using "Update Catalog," user can also narrow down database queries by specifying query criteria and/or specifying specific realtor
• Salesman sends single gathering agent to each realtor specified by user
• A single gathering agent jumps to each requested realtor's machine, queries the realtor's database using the user's criteria, and jumps back to user's machine with the thumbnails of houses that fit the criteria

Catalog Picture 2

Demo Picture 3

Map Picture 3

• User can purchase house by clicking "Order" and clicking on thumbnail of house desired
• Salesman creates purchasing agent with the necessary monetary funds as an agent parameter
• Purchaser jumps to arbiter and realtor who is marketing the desired house opens communcation with the arbiter
• Before transaction occurs, both salesman and realtor give money to the arbiter as collateral
• After realtor receives money from purchaser, realtor gives money to bank to check for counterfeit
• If both salesman and realtor are satisfied with transaction, each sends an ok message to the arbiter and the arbiter returns the money given as collateral
• Purchaser returns after transaction completed

Map Picture 4

• If purchase was successful, the user obtains full picture of the house purchased (full picture obtained by salesman during intial queries to realtors)

Purchase Picture

*Pictures of all houses are copyrighted by McLaughry Real Estate and are used in the Realtor Demo for demonstration purposes only