Robtex

Up: 123.205.240.0/20
Can't show all results, try to descend to a more specific CIDR
Down left: 123.205.248.0/22
Down right: 123.205.252.0/22

IP	Type	Hostname
123.205.248.0	PTR	123-205-248-0.static.seed.net.tw
123.205.248.5	PTR	123-205-248-5.static.seed.net.tw
123.205.248.116	PTR	123-205-248-116.static.seed.net.tw
123.205.249.132	PTR	123-205-249-132.static.seed.net.tw
123.205.250.76	A+PTR	123-205-250-76.adsl.dynamic.seed.net.tw
123.205.250.76	A	r1.sn-45gx5nuvox-u2xk.googlevideo.com
123.205.250.77	A+PTR	123-205-250-77.adsl.dynamic.seed.net.tw
123.205.250.77	A	r2.sn-45gx5nuvox-u2xk.googlevideo.com
123.205.250.78	PTR	123-205-250-78.adsl.dynamic.seed.net.tw
123.205.250.79	PTR	123-205-250-79.adsl.dynamic.seed.net.tw
123.205.250.80	A+PTR	123-205-250-80.adsl.dynamic.seed.net.tw
123.205.250.80	A	r5.sn-45gx5nuvox-u2xk.googlevideo.com
123.205.250.82	A+PTR	123-205-250-82.adsl.dynamic.seed.net.tw
123.205.250.82	A	r7.sn-45gx5nuvox-u2xk.googlevideo.com
123.205.250.83	PTR	123-205-250-83.adsl.dynamic.seed.net.tw
123.205.250.123	A+PTR	123-205-250-123.adsl.dynamic.seed.net.tw
123.205.250.155	A+PTR	123-205-250-155.adsl.dynamic.seed.net.tw
123.205.250.187	A+PTR	123-205-250-187.adsl.dynamic.seed.net.tw
123.205.251.38	PTR	123-205-251-38.adsl.dynamic.seed.net.tw
123.205.251.42	A+PTR	123-205-251-42.adsl.dynamic.seed.net.tw
123.205.251.44	A+PTR	123-205-251-44.adsl.dynamic.seed.net.tw
123.205.251.45	A+PTR	123-205-251-45.adsl.dynamic.seed.net.tw
123.205.251.46	PTR	123-205-251-46.adsl.dynamic.seed.net.tw
123.205.251.49	A+PTR	123-205-251-49.adsl.dynamic.seed.net.tw
123.205.251.52	A+PTR	123-205-251-52.adsl.dynamic.seed.net.tw
123.205.251.78	PTR	123-205-251-78.adsl.dynamic.seed.net.tw
123.205.255.255	PTR	123-205-255-255.adsl.dynamic.seed.net.tw