First post, so I apologize if I don't lay things out clearly, or if this is the wrong forum.
We are a small/regional ISP. We have a customer who has a couple of /24s (not purchased through us), and they would like us to announce these /24s to our upstream providers. However, they do not want to BGP peer with us (cost-savings, configuration, etc...). We've received an LOA from them, giving us permission for this, and we've passed it along upstream.
We are happy to do this, but the problem is the advertisement is getting blocked further upstream. The larger transit providers appear to be querying the radb for their prefix lists, which is a problem as the radb has the /24s under the customer AS. So, if we try to advertise the /24s with our AS, they are getting dropped by these larger providers.
We are curious as to what other ISPs are doing in situations like this? Do you ask the customer to SWIP the /24 over to the ISP AS? Does the ISP turn up a BGP instance with the customer AS in order to spoof it (seems non-kosher)? Or something else entirely?
We don't have the IP space available to give them a /24, and the customer does not want any type of BGP relationship.
Appreciate any response.