2002 - cesnet

sible reprogramming of functions, also applicable at the end user‘s site and areasonable price. These requirements were ideally fulfilled by the technologyof field-programmable gate arrays (FPGA).During the initial stage of the project, it was our plan to make use of commerciallyavailable boards with FPGA circuits for the accelerator, complementedby an interface board designed by us. However, we carried out market researchand found out that commercially available boards were not up to our requirementsand that the price for these boards was also relatively high. We thereforedesigned our own hardware accelerator, COMBO6 (COmmunication MultiportBOard for IPv6), and made arrangements for its production.The designed COMBO6 card includes the following electronic circuits:• A gate array of VIRTEX II family, produced by Xilinx,• SRAM, CAM and DDRAM memory,• PCI interface circuits,• Communication port interface circuits,• Power supply and auxiliary circuits.The accelerator is divided into two interconnected parts:1. Basic PCI card,2. Communication interface card, connected with the basic card through aconnector.The advantage of this solution is the separation of the technologically complicatedmotherboard and the relatively simple interface board. If another typeof interface is required (optical, metallic), we need not develop the entire cardagain, it is enough just to design a new interface card instead.The entire project is designed as fully open with public access to all information.The COMBO6 card will, therefore, also be available for other projects. WeFigure 5.3: COMBO6 motherboardHigh-speed National Research Network and its New Applications 200273