Thursday, October 26, 2000
The PCI bus is the standard peripheral interface used with
A microprocessor can run the "brains" of a computer, but all that
calculating power is useless unless it can communicate with users and other
computers. So when the CPU needs to talk to its peripheral devices (the network
connection, disk drive, video display, sound board, etc.), it communicates over
the PCI (peripheral component interconnect).
In accordance with Moore's Law, computing power has been roughly
doubling every 18 months, but the PCI has been used for nearly a decade. So this
week, developers announced a new peripheral interface called InfiniBand™.
On Tuesday, the InfiniBand Trade Association (IBTA, www.infinibandta.org) unveiled version
1.0 of the nascent specification for this input/output technology. Originally
known as System I/O, InfiniBand can use both copper wire and optical fibers. It
also differs from PCI by using a point-to-point switching architecture. This
arrangement unlinks the I/O subsystem from the memory by using channel-based,
point-to-point connections rather than combining the bus, load, and store
functions. And it permits InfiniBand to attain data transfer rates of 500 MBps
to 6 GBps.
Compared to current systems, standard PCI runs at 33 MHz, and
supports both 32- and 64-bit data paths. PCI version 2.1 will run at 66 MHz. And
another bus called ISA (industry standard architecture) runs a 16-bit data path
and is on the path to obsolescence.
The InfiniBand standard is supported by an association of seven
computer companies: Compaq, Dell, Hewlett-Packard, IBM, Intel, Microsoft, and