<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph
{mso-style-priority:34;
margin-top:0in;
margin-right:0in;
margin-bottom:0in;
margin-left:.5in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
p.msonormal0, li.msonormal0, div.msonormal0
{mso-style-name:msonormal;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
span.EmailStyle18
{mso-style-type:personal-reply;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
/* List Definitions */
@list l0
{mso-list-id:1638955422;
mso-list-type:hybrid;
mso-list-template-ids:-129456038 67698711 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;}
@list l0:level1
{mso-level-number-format:alpha-lower;
mso-level-text:"%1\)";
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level2
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level3
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level4
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level5
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level6
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level7
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level8
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-.25in;}
@list l0:level9
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal">To a certain extent, faster Ethernet is more likely to be a commodity – and at rates above 1 Gbps, there’s substantial “art” in making a PHY that works reliably. At the 10G speed, there’s things like RapidIO and SRIO, but they
<o:p></o:p></p>
<ol style="margin-top:0in" start="1" type="a">
<li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1">Only work for short distances (<<1 meter)<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1">Are *<b>very</b>* board layout and other implementation sensitive. Fine for getting in and out of a package, but not great for running any distance.<o:p></o:p></li></ol>
<p class="MsoNormal">Then there’s XAUI (pronounced Zowie!) which is a multiwire wire interface between logic and 10G (or whatever) PHY. But it’s got the same problems as SRIO/RapidIO (or for that matter, the venerable (now) TLK2711 SERDES).
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">10G and 40G Ethernet do actually work over distances of meters, and over some moderate range of temperatures, and are likely to meet EMI/EMC requirements.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It is interesting that there doesn’t seem to be the same commercial pressure for optical versions. They all exist, but typically as modules you’d slide into your switch, not components you’d solder to a board. And there are plenty of XAUI->optical
kinds of interfaces. And optical cables are cheap and relatively rugged. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>From:</b> Beowulf <beowulf-bounces@beowulf.org> <b>On Behalf Of
</b>Scott Atchley<br>
<b>Sent:</b> Wednesday, January 17, 2024 7:18 AM<br>
<b>To:</b> Larry Stewart <stewart@serissa.com><br>
<b>Cc:</b> Mark Hahn <hahn@mcmaster.ca>; beowulf@beowulf.org<br>
<b>Subject:</b> [EXTERNAL] Re: [Beowulf] anyone have modern interconnect metrics?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal">While I was at Myricom, the founder, Chuck Seitz, used to say that there was Ethernet and Ethernot. He tied Myricom's fate to Ethernet's 10G PHYs.<o:p></o:p></p>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<div>
<p class="MsoNormal">On Wed, Jan 17, 2024 at 9:08 AM Larry Stewart <<a href="mailto:stewart@serissa.com">stewart@serissa.com</a>> wrote:<o:p></o:p></p>
</div>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in">
<p class="MsoNormal" style="margin-bottom:12.0pt">I don't know what the networking technology of the future will be like, but it will be called Ethernet.<br>
- unknown (to me)<br>
<br>
<o:p></o:p></p>
</blockquote>
</div>
</div>
</body>
</html>