Robtex

Up: 194.121.216.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 194.121.220.0/23
Down right: 194.121.222.0/23

IP	Type	Hostname
194.121.221.13	PTR	194-121-221-13.de.kpn-eurorings.net
194.121.222.1	PTR	194-121-222-1.de.kpn-eurorings.net
194.121.222.118	PTR	194-121-222-118.de.kpn-eurorings.net
194.121.222.233	PTR	194-121-222-233.de.kpn-eurorings.net
194.121.223.58	PTR	194-121-223-58.de.kpn-eurorings.net