[lir-wg] AS Number Policy

On Thu, 11 Jul 2002, Kurt Erik Lindqvist wrote:

>
>
> --On Tuesday, July 09, 2002 15:57:49 -0400 "Lu, Ping" <PLu at cw.net> wrote:
>
> > Several examples:
> >
> > 1. Confederate AS : only the top level AS number is announced by design,
> > all member ASes should not be visible outside the confederate.
>
> Which by desing should be done with private as:es. It's more or less in the
> instruction book.
>
> > 2. CIDR aggregate : If customer's address got aggregated by upstream ISP,
> > usually you won't see their AS numbers from the upstream ISP's CIDR
> > (especially for those people like to filter on allocation boundary).
>
> I am lost. If customer routes are aggregated by upstream, I assume the
> customer don't have an AS? If the customer have an AS and is multihomed you
> might aggregate his addresses, but you will still see the originating AS in
> the AS-path (or through the other path - as the customer won't get an AS
> unless he is multihomed).


A customer can have a peer with the default transit, which aggregates the
adresspace from the customer, and the customer can have other peerings
via some ix:es, and the customer could perform transit to/from the ix:es
to the default transit, in this scenario the customer MUST have a public
AS, which you will not see in the public space, since removing private
AS in the AS-path will result in somewhat unpredictable behaviour if there
are several private AS involved at the customer premises.


>
>
> > Technically I don't see how RIPE NCC can possibly find all the ASes that
> > are originated but invisible to the public route server.
>
> I can't see how people should/could/would need AS:es from the public space
> that is not visible in the public space.
>
> - kurtis -
>

-- 

Mvh

	/Fredrik

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