Hi all,

Support adoption. I am willing to contribute ‘RPKI Signed Object’ and ASN.1 
text - when the time comes and if desired.

In relation to Sriram’s remark:

> On 25 May 2018, at 16:56, Sriram, Kotikalapudi (Fed) 
> <[email protected]> wrote:
> 
> 2.  I would prefer that the proposed new RPKI objects contain only a list of 
> immediate customers.
>> From that (assuming mature state of deployment), the entire customer AS cone 
>> for
> any AS can be constructed (recursively). 
> I see a major down side to including more than the list of immediate 
> customers.
> The downside is that there could be too much churn in the RPKI.
> If a customer drops or changes a transit provider, then there should not be 
> any ripple effects
> in the RPKI propagating through all higher tiers.  I think this rippling 
> effect is inherent
> with the current proposal in the draft (as I understand it). 

Quick grepping in the RIPE Database IRR shows that about 15% of “members:” 
attributes in AS-SET objects references other AS-SET objects. This could be 
other people’s customers, or it could be shorthands (allowing easy re-use of a 
set of ASNs in different places). When it’s other people’s customers then it’s 
not clear to me whether the ASN that makes this reference would still appear in 
the PATH. In other words, could one not just stick to referencing ASNs only and 
recursively find the published ‘rpki-as-cone' for those ASNs?

If only ASNs are used, I do believe that the object can be simplified and it 
would be much easier to reason about who signs what. There could be a single 
object per AS:

Policy for AS-A

To-upsteam: AS-X, send customers: AS1,2,3
To-upsteam: AS-Y, send customers: AS 4, 5
To-upsteam: AS-Z, send customers: none

Signed AS-A (must appear on EE certificate in the RPKI Signed Object that 
contains this)

And AS 1,2,3,4,5 would each have their own rpki-as-cone object.

Unless I am missing something here (and please enlighten me if so), I think 
this would allow for building recursive lists of ASNs that may be seen on a 
session with a downstream AS, and ROAs and/or IRR objects could be used then to 
get the filterlists. At least that’s how I understand AS-SET objects to be used 
today (again, enlighten me if not.. still learning about hands-on operations).

These objects could also be leveraged through a future rkpi-rtr extension and 
allow for: valid/invalid/unknown upstream|downstream hooks in router config.

Meaning:
1) if a given AS-A did not publish an rpki-as-cone object, then both upstream 
and downstream ASNs would be UNKNOWN relative to this AS-A.
2) if a given AS-A published an rpki-as-cone object with AS X,Y, and Z as 
upstreams then AS-A->ASX/Y/Z in a path would be VALID, while AS-A->any other AS 
would be INVALID upstream
3) if a given AS-A published an rpki-as-cone object with AS 1,2,3 as customers 
to AS-X, then AS1/2/3->AS-A would be VALID where (AS-A->AS-X), and any other 
AS->AS-A here would be INVALID (undeclared customer for upstream)

This would allow for semantics like:
If (path contains INVALID upstream) or (path contains undeclared customer) or 
(origin invalid [ROA origin validation) then drop

It would also allow for incremental uptake. Any AS can protect themselves a bit 
better by publishing a signed policy, but if you don’t then there is no 
difference from today. RPKI Validators can do the leg work for the crypto, so 
implementation in routers would require some memory and CPU, but nothing too 
drastic - similar to rpki-rtr and ROAs today.

Tim






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