Compaq OSI/FTAM D43, OSI/APLMGR D43 manual Compaq Ftam Responder Operation, Responder Structure

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Compaq FTAM Responder Operation

The Compaq responder receives an FTAM request from an initiating system, processes it, performs the appropriate action, and returns an FTAM response to the initiating system. It performs file-handling operations through its virtual filestore (VFS), which acts as an interface to the Guardian file system.

This section explains the major components of the Compaq responder process and describes the flow of communication between an initiating system and the Compaq responder.

Responder Structure

The Compaq responder process can be broken down into several components that perform services for FTAM applications.

Figure 3-1 outlines the components of the responder that process FTAM requests, perform the requested FTAM operations, and respond to the remote FTAM user. It focuses on the responder components specific to performing FTAM services and does not reflect the parts of the responder that format data or process management messages, for example.

Figure 3-1 shows the following responder components:

•The protocol state machine receives requests for new FTAM associations and for FTAM services, in the form of indications, from the TAPS process in the OSI/AS subsystem. It checks the FTAM requests for protocol errors, and if it finds none, takes the action necessary to perform the requested service. This action may require access to the file system through the responder VFS component.

Once any operations involving the file system are complete, the protocol state machine updates the state information for the association and sends a response to the remote FTAM initiator via the underlying OSI network.

•The virtual filestore (VFS) acts as an interface to the file system. Files accessible via the file system can also be accessed via the VFS component of the Compaq responder. The VFS is responsible for translating file structures and attributes into FTAM file structures and attributes, and vice versa. This translation is described further in Section 4 under “File-Attribute Mappings.”

•The responder communicates with underlying Compaq OSI/AS processes through the OSI/AS API.

OSI/FTAM Responder Manual—425199-001

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