I'm trying to figure out how to determine the routes acceptable by a certain AS network by reading its export/import attributes. It may work in some networks that has these headers but some other networks simpley lack this information. lets take AS11559 for instance i use the whois command:
whois -h whois.radb.net -p 43 AS11559
% No entries found for the selected source(s).
but when i use a web tool like Hurricane Electric's bgp search( found here: http://bgp.he.net/AS11559# ) i can see that in the peer list it find these:
Rank Description IPv6 Peer 1 Sprint United States AS1239 2 Verizon Business/UUnet United States AS701
so two questions comes in mind:
- Why some ASN networks do not contain IRR records?
- How do Hurricane electric manage to retreive this data?
- Is there a better(and native, not scraping) way to retrieve the routing topology of an AS network?
Many thanks in advance :)