On 2014-12-22 15:45, Song Li wrote:
在 2014/12/22 22:26, Nick Hilliard 写道:
On 22/12/2014 13:50, Jeroen Massar wrote:
IXs themselves do not have ASNs, as they are Layer 2 providers.
most modern IXPs will have an ASN for their route server, and possibly a separate asn for their mgmt infrastructure.
Not sure how useful the mgmt ASN is, although most IXPs will paradoxically include this on their list of members.
Nick
Thanks for your help!
I studied all the AS-Path in the routing table (from routeviews and RIPE), and found that some ASN of IXPs were included in some AS-Path.
You are likely seeing IP addresses from the peering LAN, which typically have addresses that are under the ASN from an IX. Quite a few IXes state that the peering prefixes should not be announced world-wide.
I think that under normal circumstances they should not appear in the AS-Path, hence i want to filter out them.
"Filtering them out" will have fun results when a valid ICMP is being returned. Something about "Packet Too Big"... What is the reason for thinking you need to filter these? Greets, Jeroen