The US Defense Advanced Research Projects Agency (Darpa)
will fund a four-year programme to develop optical interconnect
technology for chip-to-chip communications, headed by researchers
at IBM and Agilent Technologies.
As processing speeds increase and server vendors pack more
processors in their systems, the existing copper interconnect
technologies that link chips in a server will become a huge
bottleneck, said Marc Taubenblatt, senior manager of optical
communications at IBM Research. Optical technology could help solve
that problem, he added.
Optical technology tends to be used in communications networks
and server-to-server connections to speed data transmission.
Instead of transmitting electrical signals down copper wires,
optical technology sends light waves over fibreoptic cables at
faster speeds, using less power than copper technology.
IBM and Agilent will work to devise ways to miniaturise that
optical interconnect technology so it can be used to connect chips
within a server, such as in the connections between the central
processing unit and the system's memory. Some optical technology is
already used in I/O buses for connecting to storage devices or
Lans.
Servers benefit from optical interconnects once data
transmission speeds reach 10Gbps per channel or greater. The team
hopes to enable bandwidth of 40Tbps between processors in a server
by the time the project is complete.
IBM and Agilent intend to demonstrate the technology within
three years, and spend the fourth year of the project demonstrating
the results within a working system.
Darpa gave the two companies $30m to conduct their research.
Tom Krazit writes for IDG News Service