At 22:05 7/28/2015 -0400, you wrote:
A couple of minor notes regarding ASNs:
Also the AS number assigned to an IP address may legitimately vary depending on the source/observer. This is due to the relativistic nature of BGP routing. For example a Comcast address 74.95.187.105 is listed in AS 33287 by CYMRU (my preferred source), but Routeviews does not see the sub-block due to BGP aggregation and puts it in 7922.
Looking-glass servers are helpful when trying to understand AS-IP assignments, here are just two of many
http://lg.he.net http://lookingglass.level3.net/
=====
Much of the above applies equally to IPv6 except that by design, the IPv6 address space is far less fragmented and very often an AS will advertise only one and never more than a handful of address blocks.