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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Hello All,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Question</span></b><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>: which of the two equations should we use in the process of the selection of cables for FDR receiver tolerance testing?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Mellanox has a question regarding the FDR receiver tolerance tests with linear cables (described in section 6.7.8.1 of the InfiniBand Architecture Specification Volume 2), specifically regarding the selection of cables for the test.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Table 55 of the InfiniBand Architecture Specification Volume 2 defines the fitted insertion loss coefficients of the cables that should be used in the tests, with a reference to clause 85.8.4.2 of the IEEE 802.3.2012 document. However, there is a discrepancy between the ways the IEEE 802.3.2012 document and the InfiniBand Architecture Specification Volume 2 define the relation between the fitted insertion loss <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>and the mentioned coefficients – the equation used in the IEEE 802.3.2012 document is<img width=187 height=28 id="Picture_x0020_3" src="cid:image007.png@01CE1A55.68747CD0"> , <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>The InfiniBand Architecture Specification Volume 2 defines the fitted insertion loss as<img width=240 height=54 id="Picture_x0020_2" src="cid:image008.png@01CE1A55.68747CD0"> , where<img width=28 height=35 id="Picture_x0020_1" src="cid:image009.png@01CE1A55.68747CD0"> is the signaling frequency (14.0625 GHz). <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Thanks<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Rupert<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p></div></body></html>