Robtex

Up: 170.72.64.0/18
Can't show all results, try to descend to a more specific CIDR
Down left: 170.72.64.0/20
Down right: 170.72.80.0/20

IP	Type	Hostname
170.72.64.132	PTR	bom01-wxpd-lb01-adns.webex.com
170.72.64.132	PTR	bom01-wxpd-lb01-v120-snip.webex.com
170.72.64.176	A	170-72-64-176.az.vivintwireless.net
170.72.65.128	A+PTR	170-72-65-128.az.vivintwireless.net
170.72.69.187	A	170-72-69-187.az.vivintwireless.net
170.72.79.132	PTR	170-72-79-132.az.vivintwireless.net
170.72.80.240	A	ed1sgcb12902.webex.com
170.72.80.245	A	ed1sgcb128.webex.com
170.72.87.23	A+PTR	170-72-87-23.az.vivintwireless.net
170.72.87.202	A+PTR	170-72-87-202.az.vivintwireless.net
170.72.89.74	A	170-72-89-74.az.vivintwireless.net
170.72.89.74	A	elpasoitdepartment.com
170.72.90.115	A+PTR	170-72-90-115.az.vivintwireless.net
170.72.91.14	A+PTR	170-72-91-14.az.vivintwireless.net