IBM Corp. and Intel Corp. are currently developing new I/O architectures aiming to change the way servers are fundamentally built.
IBM's Future I/O and Intel's Next Generation I/O (NGIO) are intended to replace the existing PCI specification for servers.
IBM's planned channel-based, or switched-fabric, design is taken directly from the mainframe model, said a source close to IBM's I/O development. The design springs from IBM's vaunted technology, the venerable S/390 mainframe.
"We would want to line up the pathway to make [channel-based I/O] an industry standard, get the right players, then mature the actual technology specs," the source said.
Meanwhile, Intel will detail its strikingly similar NGIO proposal next week at the Forum on Next Generation I/O for Servers, in San Diego.
One analyst noted that PCI development is lagging behind rapid advances in processing power.
"PCI is definitely not keeping up," said Jerry Sheridan, director and principal analyst at Dataquest, in San Jose, California.
PC OEMs were sanguine about the forthcoming channel-based I/O specifications.
"We do support switched-fabric architectures. They have some advantages," said Karl Walker, vice president of technology development at Compaq's Enterprise Computing Group, in Houston.
Chris Dodd, manager of I/O and cluster architecture at Intel's Server Architecture Laboratory, in Hillsboro, Oregon, calls IBM's S/390 channel design the "reference standard" for server I/O. Intel plans to use technology from that architecture for next-generation servers.
More point-to-point links will replace the bus-oriented architecture of today's PCs, Dodd said. A switched fabric will replace multiple buses.
Multiple CPUs will continue to hang off a host bus, but this bus will communicate with the rest of the system only through a host channel adapter (HCA). The HCA links through the multistage switched fabric to target channel adapters, or TCAs, that in turn connect through I/O controllers to Gigabit Ethernet, Fibre Channel, SCSI, or other I/O channels.
Today's architecture requires bridges from one bus to another and a shared I/O bus, creating two performance bottlenecks.
After incorporating feedback from hardware developers and others, Intel will publish a final specification and offer royalty-free licenses to prospective OEMs, said Tom Macdonald, marketing director for the enterprise server group at Intel, in Hillsboro.
Macdonald pointed out that the NGIO specification does not require a specific CPU architecture, and could be used in servers based on non-Intel processors. For example, Sun could use Sparc and Compaq could use Alpha to drive servers that are built around the NGIO specification.
IBM Corp., in Armonk, New York, can be reached at www.ibm.com. Intel Corp., in Santa Clara, California, can be reached at www.intel.com.