Re: [Sidrops] On validating AS paths

Christopher Morrow <> Mon, 01 July 2019 18:27 UTC

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From: Christopher Morrow <>
Date: Mon, 1 Jul 2019 14:27:27 -0400
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To: Iljitsch van Beijnum <>
Cc: Alexander Azimov <>, SIDR Operations WG <>
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Subject: Re: [Sidrops] On validating AS paths
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On Mon, Jul 1, 2019 at 9:47 AM Iljitsch van Beijnum
<> wrote:
> Yes. Note that in my previous message I was specifically addressing validating the _entire_ path, while ASPA only concerns itself with validating the "up" part of the path, where the only valid relationships are provider-customer and sibling-sibling.

isn't this the point of 'bgpsec'? meaning: "you can do this when you
see bgpsec signed paths from bgp peers"

> Of course once we can validate the entire path, we can by definition also validate any subset.
> And of course, a path //^\ (in your notation) received from customer or peer is invalid. But I assume that you also had this in mind.