Optical Right down to the Silicon


As the IT universe contemplates 10G, 40G and even 100G networking, little notice is being given to the new generations of fiber optic technology that will make it all happen, or to the ways in which fiber is set to radically remake the very nature of computing itself.


The latest chipsets are combining multiple amplifiers with Vertical Cavity Surface Emitting Laser (VCSEL) technology that boost bandwidth and lower power consumption for a wide range of High-Performance Computing (HPC) and Very Short Reach (VSR) communications applications. GigOptix has one of the newest devices on the market, a 4x10.3 Gbps SiGe (silicon-germanium) chipset that pairs four of the company's Transimpedence Limiting Amplifiers (TIA/LA) with four VCSEL drivers on a standard 2-wire interface using the Quad Small Form Factor Pluggable (QSFP) design. The company is eyeing the device for Ethernet and Infiniband transceivers, as well as active cables and multichannel optical modules.


The rise of optical interconnects and VCSEL diodes are set to drive the multimode connector market past the $1 billion mark within the next year or so, according to research from ElectroniCast Consultants. The group expects that market to nearly double to $1.4 billion by 2012, driven largely by the rapid expansion of fiber into enterprise LANs.


But that's only half the story. Copper has long been a fixture of the typical workstation, even though it is electrically unstable, draws a lot of power and is very noisy. Connecting processor cores to on-chip systems through optical interconnects, a technology known as photonics, promises to greatly speed up the computer and possibly cut power requirements in half, according to this report from Cliff Saran. Techniques currently under investigation would do away with the binary "on/off" system of copper and replace it with multiple laser bitstreams.


Intel is pushing this technology the farthest at the moment, demonstrating a design that puts up to 200 Gbps on a single beam, twice as fast as current optical networking technology. The company is looking to combine up to 25 40-Gbps modulators onto a single chip to get the data rate up to a terabit or more.


The implications of this kind of technology are vast. Forget about Moore's Law. Photonics has the potential to push processing capabilities beyond the imagination. And it could be a commercial reality within the next decade.