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how to hide my AS number












ISP1 =1

ISP2 = 2

ISP3 = 3


Customer1 = 5

Customer2= 6

ISP1, ISP2, and ISP3 are the same level. There are incterconnectivity between them that is not in the diagram only ISP1 and ISP2. Customer1 is peering with me for their internet connectivity with Customer2. I'm peering with ISP1 and ISP3. ISP1 claim that ISP2 might block me in the future because they might found out that I'm also an ISP. According to ISP1 I should hide my AS so that ISP2 will not see it but my prefix is still routable to ISP3. Of course whatever the configuration is, the AS I'll be peering to ISP3 is still AS4. Peering to Customer1 will also AS4 or whatever in case that there is a solution for this. ISP1 claims that I could either use BGP Confederation or use private AS, I don't see any feasibility on this unless I connect only to ISP1 and not to ISP3 anymore. What is your view?


Re: how to hide my AS number

Your request is very difficult to respond to for at least two reasons:

1 - Your appear to be asking for help to violate the terms of a legitimate contract. A technical solution to a business problem.

2 - Your definition of the problem is appears incomplete. Customers 1 and 2 should only have their own ASN's if they too are multihomed. In which case, how can ISP2 distinguish them as "legitimate" downstream customers from you as an "illegitimate" downstream ISP?

Note that there are ways to "hide" your ASN, but they have severe side effects (such as defeating BGP routing loop detection) and should not be trifled with without a solid understanding of the full application environment, failure recovery requirements, and how the protocols work.

Good luck and have fun!

Vincent C Jones

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