Robtex

Up: 208.64.200.0/23
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Down left: 208.64.200.0/25
Down right: 208.64.200.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
208.64.200.1	PTR	208-64-200-1.steampowered.com
208.64.200.4	PTR	208-64-200-4.steampowered.com
208.64.200.7	PTR	208-64-200-7.steampowered.com
208.64.200.8	PTR	208-64-200-8.steampowered.com
208.64.200.9	PTR	208-64-200-9.steampowered.com
208.64.200.10	PTR	208-64-200-10.steampowered.com
208.64.200.10	A	partnerupload0.steampowered.com
208.64.200.17	PTR	208-64-200-17.steampowered.com
208.64.200.17	A	cloud-origin.steampowered.com
208.64.200.17	A	video.steamstatic.com
208.64.200.22	PTR	208-64-200-22.steampowered.com
208.64.200.29	PTR	208-64-200-29.steampowered.com
208.64.200.30	PTR	208-64-200-30.steampowered.com
208.64.200.30	A	cdn.steamstatic.com
208.64.200.30	A	cdn-01-origin.steampowered.com
208.64.200.35	PTR	208-64-200-35.steampowered.com
208.64.200.39	PTR	208-64-200-39.steampowered.com
208.64.200.39	A	hl2master.steampowered.com
208.64.200.49	PTR	208-64-200-49.steampowered.com
208.64.200.51	PTR	208-64-200-51.steampowered.com
208.64.200.52	PTR	208-64-200-52.steampowered.com
208.64.200.52	A	hl2master.steampowered.com
208.64.200.58	PTR	208-64-200-58.steampowered.com
208.64.200.65	PTR	208-64-200-65.steampowered.com
208.64.200.65	A	hl2master.steampowered.com
208.64.200.83	PTR	208-64-200-83.steampowered.com
208.64.200.85	PTR	208-64-200-85.steampowered.com
208.64.200.92	A	dns2.thisgeek.com
208.64.200.100	PTR	208-64-200-100.steampowered.com
208.64.200.100	A	*.asterlink.com
208.64.200.100	A	www.asterlink.com
208.64.200.101	PTR	208-64-200-101.steampowered.com
208.64.200.102	PTR	208-64-200-102.steampowered.com
208.64.200.105	PTR	208-64-200-105.steampowered.com
208.64.200.105	A	gds4.steampowered.com
208.64.200.105	A	gds2.steampowered.com
208.64.200.117	PTR	208-64-200-117.steampowered.com
208.64.200.117	A	hl1master.steampowered.com
208.64.200.118	PTR	208-64-200-118.steampowered.com
208.64.200.118	A	hl1master.steampowered.com
208.64.200.127	PTR	208-64-200-127.steampowered.com
208.64.200.129	PTR	208-64-200-129.steampowered.com
208.64.200.137	PTR	208-64-200-137.steampowered.com
208.64.200.143	PTR	208-64-200-143.steampowered.com
208.64.200.160	PTR	208-64-200-160.steampowered.com
208.64.200.189	PTR	208-64-200-189.steampowered.com
208.64.200.190	PTR	208-64-200-190.steampowered.com
208.64.200.191	PTR	208-64-200-191.steampowered.com
208.64.200.192	PTR	208-64-200-192.steampowered.com
208.64.200.201	PTR	208-64-200-201.steampowered.com
208.64.200.202	PTR	208-64-200-202.steampowered.com
208.64.200.203	PTR	208-64-200-203.steampowered.com
208.64.200.204	PTR	208-64-200-204.steampowered.com
208.64.200.205	PTR	208-64-200-205.steampowered.com
208.64.200.231	PTR	208-64-200-231.steampowered.com
208.64.200.231	A	partnerupload1.steampowered.com
208.64.200.240	PTR	208-64-200-240.steampowered.com
208.64.200.243	PTR	208-64-200-243.steampowered.com
208.64.200.249	PTR	208-64-200-249.steampowered.com
208.64.200.252	A+PTR	sdr-01.valve.net