Some of the most important features and benefits of the i960 RP and RD I/O processors include:

	Increased performance
	More capabilities
	Highly integrated design

Increased Performance
Intel’s i960® RP I/O processor can increase overall system performance by offloading the routine I/O functions ordinarily handled by the host processor. It also creates a secondary PCI bus to move I/O activity off the primary PCI bus, reducing data congestion.

In a conventional system without an I/O processor, the host processor must handle every I/O interrupt, consuming critical clock cycles waiting for slow I/O devices like hard disk drives to return data.

An Intelligent I/O subsystem with an Intel I/O processor relieves the host processor from the burdens of handling all the I/O interrupts. This means that more clock cycles are now available to focus on the critical application software that your server was purchased to run.

More Capabilities
The i960 I/O processors are a great tool for creating designs which can increase system throughput while adding new capabilities and freeing host CPU power for application processing.

In RAID subsystems, designers can use an Intel I/O processor to control the parallel transactions and compression algorithms, rather than requiring an expensive, proprietary controller. Overall system cost can be significantly reduced with the Intel I/O processor directly on the motherboard, while using a standard SCSI interface.

Another promising area for increasing server performance is peer-to-peer technologies. An example would be designing a disk-to-LAN interface, providing a more direct, high-throughput data path using an Intel I/O processor to handle data flow and keep traffic off the primary PCI bus. Revision 1.5 of the I₂O* specification provides support for peer-to-peer implementations.

System management is coming to the forefront as an important tool in reducing total cost of ownership. Servers equipped with an Intel I/O processor can be outfitted with a system management agent such as Patrol* from BMC software which collects system data and statistics, adjusts operating parameters, processes updates and centralizes enterprise management. And all this can run on the I/O processor, without draining the host CPU and detracting from its data processing.

Highly Integrated Design
The i960 RP/RD I/O processors integrate the functions necessary for an Intelligent I/O subsystem on a single chip. This subsystem includes an i960 JF processor core, a PCI-to-PCI bridge, an address translation unit, messaging unit, PCI arbiter, DMA controller, integrated memory controller, APIC interface, I²C interface and interrupt routing.

The PCI-to-PCI bridge creates an electrically isolated PCI bus, enabling direct connection of I/O devices and the capability to add additional PCI connections. The bridge isolates PCI transactions initiated on and intended for the secondary PCI bus, thus reducing traffic on the primary PCI bus.

The i960 RP/RD I/O processor's messaging unit provides for the transfer of data between the PCI bus and the I/O processor and notification of interrupts. The unit allows for message registers, doorbell registers, circular queues and index registers. The integrated DMA unit provides three channels for high-throughput memory transfer. The i960RP I/O processor's APIC interface allows it to steer interrupts to the other processors.

As a result of this integrated design, high-performance Intelligent I/O subsystems are much more easily and efficiently implemented. The high level of integration also means lower implementation costs.