Copyright © TIBCO Software Inc. All Rights Reserved
Copyright © TIBCO Software Inc. All Rights Reserved


Chapter 10 Network Communication : TIBCO iProcess Workspace and TIBCO iProcess Engine Network Communication

TIBCO iProcess Workspace and TIBCO iProcess Engine Network Communication
This section provides a brief overview of how the TIBCO iProcess Workspace and TIBCO iProcess Engine communicate with each other via the network.
The TIBCO iProcess Workspace makes Remote Procedure Calls (RPC) to the server using ports. This means the TIBCO iProcess Workspace makes calls to the TIBCO iProcess Engine to find out information such as what work queues and work items it needs to display. It also means that procedures can be started from one computer but actually be running on another computer on the network. There are a number of reasons why this might happen:
Any program that offers functions that can be remotely accessed via RPC must have a unique RPC number. The RPC number for a service is either pre-defined (fixed) or allocated dynamically.
All RPC numbers need to be bound to network ports before remote clients can communicate with the RPC servers. This is because the port is the fundamental method of communication between computers.
The allocation of ports, similar to the allocation of RPC numbers, can be fixed or dynamic and is determined by the program providing the RPC service and the operating system. Therefore, it is important to know the distinction between RPC ports and numbers.
Function of a Portmapper
The connection between the RPC client computers and RPC servers is serviced by a program known as the portmapper (or rpcbind). The portmapper provides a directory for the RPC services on the computer on which it runs.
A client application can request a connection to an RPC service by passing the portmapper the RPC number. The portmapper responds by sending back the actual port number that the service is bound to. The client can then connect directly to the service using the service’s port.
The TIBCO iProcess Engine RPC Service
The process that monitors the RPC calls that request a connection to the TIBCO iProcess Engine is known as the RPC listener. This has a pre-defined RPC number - by default it is 391875. If a TIBCO iProcess Engine is communicating with another TIBCO iProcess Engine, the default port is 391870. The SWDIR\swdefs file contains the RPC numbers.
When the iProcess Engine starts:
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The following describes what happens when an TIBCO iProcess Workspace  connects to an iProcess Engine:
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TCP/IP
The RPC listeners and TIBCO iProcess Workspace use the TCP/IP protocol to communicate. In order for the TIBCO iProcess Workspace to communicate with the RPC listener processes, the TIBCO iProcess Workspace must be able to perform HOST name resolution. This means that data packets are sent to a host name such as HERCULES rather than to an IP address such as 10.10.56.202 and the TCP/IP stack looks up the correct IP address. A typical way of setting this up is to use a HOSTS file on each computer which provides a simple look up table for a host name and its IP address.
Internet Protocol Version
 

Copyright © TIBCO Software Inc. All Rights Reserved
Copyright © TIBCO Software Inc. All Rights Reserved