<div dir="ltr">Mark,<div><br></div><div>> The standard already exists... "NO_EXPORT". <br></div><div><br></div><div>I don't think this is the ask here. </div><div><br></div><div>Today NO_EXPORT takes no parameters. I think it would be of benefit to all to be able to signal NO_EXPORT TO ASN_X in a common (std) way across all of my peers connected to ASN_X. Moreover policy on all vendors could understand it too without you worrying to match YOUR_STRING and translate into some local policy. </div><div><br></div><div>That is by no means taking away anything you have at your fingertips .. it just adds an option to talk common policy language. </div><div><br></div><div>Cheers,</div><div>R.</div><div><br></div><div><br></div><div><br></div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Sep 8, 2020 at 6:23 PM Mark Tinka via NANOG <<a href="mailto:nanog@nanog.org">nanog@nanog.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div>
<br>
<br>
<div>On 8/Sep/20 17:55, Douglas Fischer via
NANOG wrote:<br>
<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small">Most of us have already used
some BGP community policy to no-export some routes to some
where.<br>
<br>
On the majority of IXPs, and most of the Transit Providers,
the very common community tell to route-servers and routers
"Please do no-export these routes to that ASN" is:<br>
<br>
</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small"> -> 0:<TargetASN></div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small"><br>
</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small">So we could say that this is a
de-facto standard.</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small"><br>
</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small"><br>
</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small">But the Policy equivalent to
"Please, export these routes only to that ASN" is very varied
on all the IXPs or Transit Providers.</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small"><br>
</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small"><br>
</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small">With that said, now comes some
questions:<br>
<br>
1 - Beyond being a de-facto standard, there is any RFC, Public
Policy, or something like that, that would define
0:<TargetASN> as "no-export-to" standard?</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small"><br>
</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small">2 - What about reserving some
16-bits ASN to use <ExpOnlyTo>:<TargetASN> as
"export-only-to" standard?</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small">2.1 - Is important to be 16
bits, because with (RT) extended communities, any ASN on the
planet could be the target of that policy.</div>
<div class="gmail_default" style="font-family:"courier new",monospace;font-size:small">2.2 - Would be interesting some
mnemonic number like 1000 / 10000 or so.<br>
</div>
</div>
</blockquote>
<br>
The standard already exists... "NO_EXPORT". Provided ISP's or
exchange points can publish their own local values to match that
within their network, I believe they can do whatever they want,
since it's locally-significant.<br>
<br>
I'm not sure we want to go down the trail of standardizing a "de
facto" usage. Just like QoS, it may be doomed as different operators
define what it means for them.<br>
<br>
Mark.<br>
</div>
</blockquote></div>