Load balancing Java instances with EP
I am wondering if EP provides load balancing when connecting to backend java systems. For example, when a user connects to the enterprise portal and then, through portal, connects to a java system like BI portal or Biller Direct, are they being load balanced? From what I have read, it sounds like the portal connects to the message server to load balance these backend systems, however I have heard some concerns that a web dispatcher instance may be needed for each backend java system. Is this true or is the load balancing functionality provided by the portal sufficient?
Our users will only be connecting to these systems via enterprise portal. We are planning to install a web dispatcher instance to balance the portal users but I am trying to figure out if more instances are needed to balance the other java systems.
I have read the help.sap.com documentation on webdispatcher, as well as these two notes, but none directly addresses this question. Experts, I would really appreciate your help!
Note 1040325 - HTTP load balancing: Message Server or Web Dispatcher?
Note 649008 - HTTP load balancing using the SAP message server