Once upon a time, James Breeden <James@arenalgroup.co> said:
I'm amazed at the number of AS numbers that are assigned, but not actively being used. I'm not talking just like they are offline for a week or month, this is complete non-use of the AS in the global routing table within *years*. They are completely abandoned resources - Whois data is inaccurate by 5-10 years, no routeviews data in the same time period, the owning organization (if you can find it) scratches their heads about responding whether they use it or not, etc.
I know of two (from a former job) that pre-date ARIN that haven't been used since 1999 because those two companies no longer exist (nor AFAIK does any successor company). The whois information is bogus at this point, but I couldn't prove that. I expect that AS numbers allocated by ARIN and other current RIRs are not abandoned like that (since they charge annual fees, and I assume they reclaim for non-payment), so the number of abandoned AS numbers is probably not growing significantly (and would not grow beyond the pre-RIR pool). With 32 bit AS numbers though, what's the point of making an effort to reclaim the old AS numbers? BGP4 has been shown to handle alternate length AS numbers, so if somehow 4 billion are allocated, it probably won't be a big deal to extend BGP again. -- Chris Adams <cma@cmadams.net>