SolutionsEngineering of technology? The answer is that FPGA technology allows for rapid modifications to, and the addition of 10 Gbit line-rate functionality. Some approaches may allow customization, but not at line rate; others may have performance while permitting little customization, but the FPGA permits a good balance of both. Some examples of added line-rate algorithm/functionality are bus/fabric protocol bridges and packet inspection/classification decisions that must be made at
line speeds (e.g., to reduce data rates by deleting packets or directing where payload data is to be sent). For small or midsized production runs, this has the appeal of enabling the same hardware system to increase its capabilities or adapt to new requirements/changes in protocols. It could be argued that the described “future proofing” flexibility offered by FPGAs, while theoretically attractive, is too far in the future to be of concern in some applications. However, the reconfig-
Figure 3
AdvancedIO System’s V1020 XMC configurable 10GbE connectivity and packet processing XMC module. The currently shipping module, which is based on the Xilinx Virtex-II PRO FPGA, supports both PCI-X and PCI Express, and is an intelligent protocol stack acceleration module.
urability of FPGA-based technology also offers a more immediate and practical derisking benefit; a benefit that can realistically make the difference between a failed or successful system integration stage. There is always a chance that a small oversight in the system specification can cause enormous delays. Suppose, for example, that the payload data coming over the 10GbE link needed to be complemented before any processing could take place on it. Although a very simple operation, it would require too many execution cycles from the processor at the incoming data rate. An FPGA placed in the high-speed path between the 10GbE link and the processor could perform this very simple customized operation on the data as it streams by. But without such a programmable device in the path before the processor, there would not be sufficient memory access or execution cycles left in the processor to accomplish it. Figure 3 shows a currently shipping intelligent 10GbE protocol stack acceleration XMC module. When integrated onto a carrier, the module’s driver software supports the use of standard socket calls by the host processor. AdvancedIO Systems Vancouver, Canada. (604) 331-1600. [www.advancedio.com].
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February 2007