"Hence, iipv6_1-lagg0-c002.1.lhr005.bt.isp.nflxvideo.net told the researchers they were talking to an IPv6 server; “lagg0” is one of various names used to distinguish the type of network connection; “c002” says there are two servers in the location delivering the content; lhr001 identifies the nearest airport (in this case, London Heathrow); the ISP is BT (“bt.isp”); “ix” reveals that the Netflix location in question is inside an Internet exchange; and nflxvideo.net is the common domain for all servers."
Well, the example given by this article doesn't have a "lhr001" in it, it has a "lhr005" (although I believe that's still Heathrow). As for "ix", I have no idea where the author pulled that from the example given.