<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=us-ascii">
<meta name="Generator" content="Microsoft Word 12 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:SimSun;
panose-1:2 1 6 0 3 1 1 1 1 1;}
@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;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:"\@SimSun";
panose-1:2 1 6 0 3 1 1 1 1 1;}
/* 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:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
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";}
span.EmailStyle18
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:windowtext;}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></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="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal"><span style="color:#1F497D">Hi Igor,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Moving the correlation from port-pair to port-pair-group makes sense. In the future I think we should add all new attributes for a SF to port-pair-group-param.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">But I think L2/L3 is different from encap type NSH or MPLS. An L3 type SF can support either NSH or MPLS. I would suggest the following:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in">port-pair-group (port-pair-group-params):<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> insertion-mode:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - L2<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - L3 (default)<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> Correlation: <o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - MPLS<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - NSH<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> tap-enabled:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - False (default)<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - True<o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Cathy<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<div>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Duarte Cardoso, Igor [mailto:igor.duarte.cardoso@intel.com]
<br>
<b>Sent:</b> Monday, March 20, 2017 8:02 AM<br>
<b>To:</b> OpenStack Development Mailing List (not for usage questions)<br>
<b>Subject:</b> [openstack-dev] [networking-sfc] About insertion modes and SFC Encapsulation<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hi networking-sfc,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">At the latest IRC meeting [1] it was agreed to split TAP from the possible insertion modes (initial spec version [2]).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I took the ARs to propose coexistence of insertion modes, correlation and (now) a new tap-enabled attribute, and send this email about possible directions.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Here are my thoughts, let me know yours:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in">1.<span style="font-size:7.0pt;font-family:"Times New Roman","serif"">
</span>My expectation for future PP and PPG if TAP+insertion modes go ahead and nothing else changes (only relevant details outlined):<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:.5in">port-pair (service-function-params):<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> correlation:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - MPLS<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - None (default)<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">port-pair-group (port-pair-group-params):<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> insertion-mode:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - L2<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - L3 (default)<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> tap-enabled:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - False (default)<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - True<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in">2.<span style="font-size:7.0pt;font-family:"Times New Roman","serif"">
</span>What I propose for future PP and PPG (only relevant details outlined):<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:.5in">port-pair (service-function-params):<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> <remove correlation – reasons outlined in [3] and below><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">port-pair-group (port-pair-group-params):<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> mode:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - L2<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - L3 (default)<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - MPLS<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - NSH<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> tap-enabled:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - False (default)<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> - True<o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">With what’s proposed in 2.:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">- every combination will be possible with no clashes and no validation required.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">- port-pair-groups will always group “homogeneous” sets of port-pairs, making load-balacing and next-hop processing simpler and consistent.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">- the “forwarding” details of a Service Function are no longer dictated both by port-pair and port-pair-group, but rather only by port-pair-group.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">Are there any use cases for having next-hop SF candidates (individual port-pairs) supporting different SFC Encapsulation protocols?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">I understand, however, that removing correlation from port-pairs might not be ideal given that it’s a subtractive API change.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">[1] <a href="http://eavesdrop.openstack.org/meetings/service_chaining/2017/service_chaining.2017-03-16-17.02.html">
http://eavesdrop.openstack.org/meetings/service_chaining/2017/service_chaining.2017-03-16-17.02.html</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">[2] <a href="https://review.openstack.org/#/c/442195/">
https://review.openstack.org/#/c/442195/</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">[3] <a href="https://github.com/openstack/networking-sfc/blob/17c537b35d41a3e1fd80da790ae668e52cea6b88/doc/source/system_design%20and_workflow.rst#usage">
https://github.com/openstack/networking-sfc/blob/17c537b35d41a3e1fd80da790ae668e52cea6b88/doc/source/system_design%20and_workflow.rst#usage</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">Best regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IE">Igor.<o:p></o:p></span></p>
</div>
</body>
</html>