OFC post-deadline talks tout terabit transmission
BEN HARRISON
Operating in a parallel, multichannel optical data link, a 5-gigabit-per-second switching module matches the processing speeds of supercomputers, advanced workstations and telecommunications switching systems. The module delivers four times greater throughput than serial technology devices and physically comprises one-third their size, according to manufacturer Vixel Corp. in Broomfield, CO.
The company, which manufactures high-speed fiber-optic communications products for Fibre Channel, Gbit/sec Ethernet and asynchronous transfer mode (ATM) applications, has shipped engineering samples of its data communications link to customers for evaluation.
This fiber-optic switching unit is being reviewed by Cray Research Inc., Tellabs Inc. and several major telecommunications equipment and supercomputer manufacturers in Japan through Vixel`s distributor, Nissho Electronics Corp.
Demand for this fiber-optic communications link is expected to increase as a result of the Telecommunications Act of 1996. This Act enables multiple vendors to compete in the same cable-TV and telecommunications territories previously under single vendor control. The rapid buildout of multiple networks is anticipated to swell demand for this communications link and other broadband-related products.
Known as the P-Vixelink (see figure), the module is a compact, simplex, multichannel fiber-optic transmitter and photoreceiver with digital input and output. It is designed for high-speed, short distances of approximately 500 meters, and for telecommunications switches and data communications. According to Vixel, each of four identical data channels can be independently accessed, and the communications link supports either synchronous or asynchronous communications.
The key enabling component in Vixel`s products is the vertical cavity surface-emitting laser, which combines the best qualities of light-emitting diodes (LEDs) and compact disk lasers.
The P-Vixelink fiber-optic communications links combine three key technologies: optoelectronic integrated circuits, high-speed analog integrated circuits for the electrical interface to the optoelectronic integrated circuits, and optical waveguides for guiding light to and from the laser diodes and detectors.
According to Greg Olbright, president and chief executive of Vixel, "This optical link increases the speed at which information is transferred by at least an order of magnitude." He claims that his company`s product is the first high-speed, Gbit/sec per channel parallel optical link. With a maximum throughput of 1.25 Gbits/sec per channel, it is possible to get an aggregate data rate of 5 Gbits/sec," Olbright says.
He also notes that Vixel has signed a letter of intent to acquire the assets and product line of Western Digital Corp.`s Fibre Channel business unit based in Lynnwood, WA. "This acquisition catapults Vixel immediately into a leadership position in the high-speed communications market for Fibre Channel, ATM and Ethernet applications."
Olbright says applications for the module are primarily in switches and networks. Manufacturers of telecommunications central office switching and computer networking equipment may find the product`s flexibility useful. On the premises side, systems currently transmit data by employing a bank of serial modules. The P-Vixelink combines these serial modules into one unit, reducing threefold the usual input/output space requirements.
Because each P-Vixelink channel is individually addressed, it can be used to transmit in synchronous mode under a timing clock, or in asynchronous mode, enabling the user to transmit signals through each channel.
Increased demand for bandwidth
Vixel has targeted the equipment segment of the telecommunications industry because growth in all services--voice or data--is ultimately concentrated for transmission and switching. The P-Vixelink product is most leveraged in the high concentration point of bandwidth. Per-line telephone bandwidth demand is forecast to increase 600% over the next five years. As aggregate throughput rates and density information increase, the move toward increased multi-Gbit/sec fiber-optics-based data transmission is expected to grow at faster rates, according to industry analysts.
Bruce Pecor, manager of the optical communications group at Cray Research Inc. in Chippewa Falls, WI, says that his organization is interested in the technology that Vixel is developing, as demonstrated by the P-Vixelink. "We certainly need this type of technology to develop high-bandwidth channels for intercabinet connections. We think that Vixel`s optical technology could make a significant contribution to the world of high-performance computing in both intercabinet and intracabinet applications." He adds that as system clock frequencies increase, Cray expects to see this type of optical technology deployed in backplane applications. q