Remote Procedure Call (RPC) Broker

Overview

The RPC Broker establishes a common and consistent foundation for client/server applications being written under the VISTA umbrella. The RPC Broker acts as a bridge connecting the client application front-end on the workstation (e.g., Delphi GUI applications) to the M-based data and business rules on the server. It serves as the communications medium for messaging between VISTAclient/server applications. Upon receipt, the message is decoded, the requested remote procedure call is activated, and the results are returned to the calling application. Therefore, the RPC Broker can be used to help bridge the gap between the traditionally proprietary VA software and Commercial-Off-The-Shelf (COTS)/Hybrid Open System Technology (HOST) products.

The RPC Broker includes:

• A common communications driver interface that handles the device-specific characteristics of the supported communications protocol.
  
  
• An interface component separate from the communications driver that interprets the message, executes the required code, and eventually returns data to the communications driver.
  
  
• A common file which all applications use to store the information on the queries to which they respond (i.e., REMOTE PROCEDURE file [#8994]).

Features

• 32-Bit Environment
  The Broker operates in a 32-bit Windows environment (i.e., client workstations running Microsoft Windows 95 or Windows NT operating systems). It also continues to support 16-bit Broker-based applications.
  
  
• Dynamic Link Library (DLL)
  The Broker provides a set of DLL functions that allow applications written in any MS Windows-based development environment (e.g., Borland's Delphi, Microsoft Visual Basic, and other COTS/HOST products), to take advantage of all the features offered by the Broker component.
  
  
• Broker Developer Kit (BDK)
  The TRPCBroker Delphi component provides Delphi developers with an easy, object-based access to the Broker. When placed on a Delphi form, it allows you to connect to the server and reference M data.
  
  
• Integrated Single Signon
  The Broker supports a single signon point from a client workstation to the server. Users need only sign on once when accessing multiple VISTAapplications on the same workstation.
  
  
• Initial Client/Server Security
  Security with the RPC Broker is a three-part process:
  • Users must have a valid access and verify code,
    
    
  • Users must be a valid users of a client/server application, and
    
    
  • Remote procedure calls must be registered and valid for the application being executed.

RPC Broker System Overview