Niall commented: #There's also services like http://www.radb.net who mirror the data from #all the IRRs who you might like to deal with! Unfortunately, at least in my experience, the routing registry data is often stale or inaccurate, even for things as basic as ASN information. This is not the fault of the RADB folks, it's simply that many users don't take the time to keep their routing registry objects up-to-date. Therefore, while some whois clients query the RADB for ASN information, in my experience, you really want to always check the RIRs for the "last word" when it comes to who controls a given resource (and of course, the sort of data that the RADB offers doesn't have the same coverage as the RIRs, anyhow). That's the main reason why I'm always concerned when I bump into, or I hear about others who've bumped into, well-intentioned but operationally-problematic whois rate limits or anti-harvesting provisions. If systems are old and underprovisioned for modern loads, my recommendation would be to make upgrading them an operational priority, or work on plans to mirror/replicate the data so that normal operational traffic isn't going to result in systems becoming slow or overloaded. Regards, Joe