Intelligent Platform Management Interface (Ipmi); Intelligent Platform Management Bus (Ipmb); Intelligent Chassis Management Bus (Icmb); Basedboard Management Controller (Bmc) - Acer Altos R710 Service Manual

Intelligent Platform Management Interface (IPMI)

IPMI stands for Intelligent Platform Management Interface. IPMI is an open standard hardware manageability
interface specification. It provides an architecture that defines how unique device can all communicate with the
CPU in a standard way.
With IPMI, the CPU has only one thing to communicate with-the IPMI Event Log. The CPU only has to "ask"
what has changed since the last time it asked. Every device communicates directly, through IPMI, to the Event
Log, which is used to record, in a consistent way, all status events for the unique device. This simplifies the
agent-handling routine. The system only needs a single agent, and it will not need to be changed when you
move from five devices to manage, for example, to six. And the system doesn't need to change the way the
CPU checks the Event Log when a new device is added to the system; it always checks in the same way,
whether there is one device or a hundred. With IPMI, use of the CPU is minimized, so overall system
performance improves.
There are four elements of IPMI: Intelligent Platform Management Interface, Intelligent Platform Management
Bus, Intelligent Chassis Management Bus, and Baseboard Management Controller. Detailed description of
each element is listed below.
Intelligent Platform Management Interface (IPMI)
IPMI is the specification for the management controller command sets, including command sets for sensors,
event logs, and sensor data record access, as well as the specification for the data formats, including sensor
data records, event log entries, and FRU inventory information. IPMI is also the name used for the overall
standardization effort.

Intelligent Platform Management Bus (IPMB)

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IPMB is the I C-based, multi-master bus used for intra-chassis communication with "satellite" management
controllers. Here sensor devices and cards with IPMI bus access can be added to the IPMI standard.

Intelligent Chassis Management Bus (ICMB)

ICMB is the RS-485 based inter-chassis management bus, based on IPMB. It is used for common chassis and
emergency management functions, including power and reset control, chassis status, events, and FRU
inventory.

Basedboard Management Controller (BMC)

BMC is used to monitor baseboard temperatures and voltages, and to manage the system event log and non-
volatile storage for sensor data records. It provides a system software interface to the Intelligent Platform
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Management Bus.
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The description of IPMI and IPMI elements is copied from IPMI's white paper, published by HEWLETT PACKARD,
in February 1998.
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