SPI Common Extensions Manual

Introduction to SPI Extensions

SPI Common Extensions Manual—427508-001

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Subsystem Control Point (SCP)

Some subsystems based on the extended SPI specification expect messages to be

routed through SCP—a process supplied by Compaq. As an intermediary, SCP can

communicate with multiple management applications and multiple subsystems.

SCP implements some of the requirements of the extended interface, and its role

includes command routing, security, and limited version reconciliation.

Each message contains the identity of the requester and the subsystem that is the

target for the message. The SCP process uses this information to forward the

message to the appropriate subsystem and route the response back to its originator.

There can be more than one SCP process. An SCP process might already exist, or it

might need to be started by your application. For details on the SCP process, see

Section 3, Subsystem Control Point, and the

Subsystem Control Point (SCP)

Management Programming Manual

Figure 1-1. The Subsystem Control Point

Note. Management applications and subsystems based on extended SPI no longer have to

communicate through an SCP process. Some subsystems require that requests are routed

through SCP. Others accept requests directly from management applications. For subsystem-

specific requirements, see the management programming manual for the subsystem.