Middleware Systems Research Group, University of Toronto, Canada

PADRES: Java Web Start

PADRES Web Start lets you to create PADRES components (broker/client/monitor) without you manually handling the PADRES binary or source code. You configure the required PADRES components and instantiate them in your computer through the web-interfaces provided below. The only thing you need for this is a fairly recent Java JRE. PADRES Web Start is platform independent.

Note: All the PADRES components are instantiated in the local machine from where you are accessing this web page. The code used for the web start is only up-to-date to summer 2010. It does not contain the latest release.

System Requirements

  • Java JRE version > 1.5

PADRES Web Start Components

You can create multiples of the same type of PADRES component using the setup interfaces given below. When you run these components, they will be invoked in the local machine. Still, you can configure them to connect to other components running on remote machines.

Broker Setup

Broker Name:
Port No.:
(e.g.: localhost:2011,


  • Broker names should be unique and can not include spaces or the dash ('-') character.
  • If a broker name is repeated, the last setup will overwrite the previous.
  • Each broker must have its own port; make sure the port is not used by any other application.
  • Neighborhood relationship between two brokers can be specified in only one Broker configuration.
  • Running a broker will produce no visible output. You have to check your process table to check whether the broker is running. Also you have to use the process table to terminate a running broker.

Client Setup

Client Name:
Broker IP:
Broker Port:


  • Client names should be unique and can not include spaces.
  • If a client name is repeated, the last setup will overwrite the previous.
  • Client names are just for the web start setup; you will not see the client names in the PADRES overlay (if one is generated later.)
  • Client can connect to a broker in a remote machine. In order to connect to a broker in the local machine, use localhost for Broker IP.



PADRES Monitor

Creating a PADRES Overlay with Web-Start

  • Decide on your PADRES overlay configuration
    • Number of brokers
    • The ports on which they are going to run
    • Number of clients
    • Who is connected to whom
  • Use the Broker Configuration form to create web start files (JNLP files) for your brokers.
  • Use the Client Configuration form to create web start files (JNLP files) for your clients.
  • Click on the "Run" links to start the overlay components. Start the brokers first before the clients.
    • Brokers are started in the background so that you will see no output when you run them. Every client will provide you with a GUI for you to interact with it.
    • If everything started correctly, client GUIs should inform you that connections to the brokers are successful.
  • You can also (optionally) start the PADRES Monitor to observe the overlay.
    • Use "Connect to federation" in the menu, and connect to one of the brokers. You can confirm that the overlay is correctly created by observing the Monitor display.

Use can verify the operation of the PADRES overlay you created by performing some publish/subscribe operations:

  • In one of the Client GUI interfaces, advertise. This is done by issueing the command:
     a [class,eq,'temp'],[area,eq,'tor'],[value,<,100]
  • In one or multiple Client interfaces, subscribe. This is done by issueing the command:
     s [class,eq,'temp'],[area,eq,'tor'],[value,<,0]
  • Lastly, in the interface that you advertised from, publish. This is done by issueing the command:
     p [class,'temp'],[area,'tor'],[value,-10]
    You should now see in the clients from where you subscribed earlier that you have received a publication.