Robtex

Up: 216.223.168.0/22
Can't show all results, try to descend to a more specific CIDR
Down left: 216.223.168.0/24
Down right: 216.223.169.0/24
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
216.223.168.0	PTR	host-0.static.gt001.gramtel.net
216.223.168.7	A+PTR	mail.gramtel.net
216.223.168.7	A	gt001.gramtel.net
216.223.168.10	A	talk.gramtel.net
216.223.168.18	A	cs002.gramtel.net
216.223.168.21	A	vpn.gramtel.net
216.223.168.30	A	csronline.com
216.223.168.59	PTR	ns.corporatesvcs.net
216.223.168.59	PTR	host-59.static.gt001.gramtel.net
216.223.168.69	A	db006.gramtel.net
216.223.168.112	A	wsbb.gramtel.net
216.223.168.113	A	wsad.gramtel.net
216.223.168.123	A	albatross.gramtel.net
216.223.168.127	PTR	host-127.static.gt001.gramtel.net
216.223.168.151	PTR	151.static.1stsource.com
216.223.168.151	A	campusbanking.com
216.223.168.151	A	1stsourceproxy.com
216.223.168.152	A	1stplanplus.com
216.223.168.154	A+PTR	smtp.1stsource.com
216.223.168.154	A	scmail.trustcorp.com
216.223.168.157	A+PTR	smtp3.1stsource.com
216.223.168.163	A	vpn.1stsourcebank.com
216.223.168.179	A	staging.1stsourceonline1.com
216.223.168.183	A	remotecapture.1stsource.com
216.223.168.185	PTR	185.static.1stsource.com
216.223.168.185	A	firstsourcebankonline.com
216.223.168.185	A	firstsourcebankmortgageloans.com
216.223.169.41	PTR	kennricci.com
216.223.169.41	PTR	mail.airgenesis.com
216.223.169.41	PTR	mail.corporatewings.com