private ASN and internet

[sarahr202]

Hi everybody

What an ISP does if it receives a bgp prefix with private asn such as 64500?  Will the isp drop it? or ISP will advertise it to its ebgp peer with AS path carrying asn 64500?

Thanks and have a great weekend.

[Reza Sharifi · Accepted solution]

Hi Sarah,

When the ISPs revive private AS from their customers, they will remove them

Have a look:

http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080093f27.shtml

HTH

[Karsten Iwen · Accepted solution]

The private ASNs will be removed before they are sent out to other SPs. Here is a guide on how it is controlled in IOS:

http://www.cisco.com/en/US/docs/ios-xml/ios/iproute_bgp/configuration/15-mt/irg-remove-as.html

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