On Tue, 9 Jul 2002, Lu, Ping 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. 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).
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 think if RIPE contacts an AS and says they are not multihomed and the AS can prove they are via some unknown LG or route server to some small local IXP that RIPE doesn't monitor - I say RIPE should record it as multihomed and close the ticket. -Hank
Ping Lu Cable & Wireless USA Network Tools and Analysis Group W: +1-703-292-2359 E: plu@cw.net
-----Original Message----- From: Vladimir A. Jakovenko [mailto:vovik@lucky.net] Sent: Tuesday, July 09, 2002 3:26 PM To: Lu, Ping Cc: 'wtremmel@vianetworks.com'; 'Matthew Robinson'; Wilfried Woeber, UniVie/ACOnet; lir-wg@ripe.net Subject: Re: [lir-wg] AS Number Policy
On Tue, Jul 09, 2002 at 02:01:26PM -0400, Lu, Ping wrote:
This has nothing to do with the private AS-number.
If an AS number existed in our backbone (public to CW) but not to RIPE NCC's route server. Will that be considered NOT USED ?
Could you possibly provide us with more examples in which circumstances someone may need to use AS number from the PUBLIC range instead of using AS number from PRIVATE range in the case when there is no need to advertise any prefixes originated by such AS-number to the PUBLIC Internet (i.e. this AS number will never be visible outside of some private network)?
I can remind only one case - some kind of IX, are used by some ASes to exchange routing information localy. Generaly speaking IX-AS may not be visible from PUBLIC, but in the most cases, especialy if we are talking about enterprise networks, same results may be achieved by using AS-number from private range.
By way of proof - AS15645 is used for the public Ukrainian Internet-Exchange. Appearance of any prefixes originated by this AS outside of IX members networks violates IX rules and should be avoided.
Lets summarise - there ARE circumstances when AS number from PUBLIC range may be requested and used being invisible from the majority of the Internet.
It would be nice to mention that in policy and provide some examples.
-- Regards, Vladimir.
Hank Nussbacher