Kevin Burt of the Samtec Optical Group walks us through one of Samtec’s product demonstrations at OFC 2017. This demo features a disaggregated computing platform with PCIe® Gen 3 fabric enabled by the patented FireFly™ mid-board optical technology. This PCIe protocol is extended outside of a standard computer bus over a distance of 100 meters.
Kevin also gives a quick primer on FireFly: it’s a very high-density, future-proof cable assembly available in both copper and optical, for chip-to-chip or board-to-board applications up to 100 meters away. The copper version is available in passive or active copper, and the optical version is available with data rates from 10 Gbps to 28 Gbps, x4 to x12, and in standard and extended temperature designs.
PCIe® Over Fiber
PCIe® over Fiber technologies enable new and emerging HPC and Data Center architectures. Traditional systems place GPUs and system storage as close to the server and CPU as possible for optimized performance.
PCIe® over Fiber technologies leverage the high performance and low latency of the PCIe® protocol, but at distances of up to 100 meters when compared to traditional copper cable assemblies. This capability gives HPC/Data Center system designs more flexibility as they design next generation solutions.
The PCIe® protocol offers many benefits to today’s system designers not offered by other fabrics: low latency, power savings, and guaranteed transmission. Traditionally, this protocol has been constrained to inside the box type applications, with some limited extension and expansion applications that use short, bulky copper cables.
FireFly™
Samtec’s FireFly™ based PCIe Over Fiber solution offers key features that solve the challenges of transmitting the PCIe protocol over longer links. The miniature size of Samtec’s high-density optical engines allows them to be easily designed into the downstream system, ultimately making these systems smaller. Highly flexible, small diameter, industry standard optical patch cords provide connection to the control system.
Other key features include:
- Gen 3 x4, scalable to x8 and x16 widths
- Support for PCIe® low power states
- Bidirectional auxiliary signals allow both transparent and non-transparent bridging
- High-performance signal quality with BER better than 1E-15
- Enables links up to 100 meters
- Enables nontraditional FPGA/ASIC-based endpoints
- Industry leading miniature footprint allows close placement to the IC, which enables lower drive voltages/pre-emphasis resulting in reduced power consumption
- Host/Target adaptor card supporting transparent and NTB links is in development