3.168.0.0/21

ip:	3.168.0.0 server-3-168-0-0.dfw59.r.cloudfront.net
loc:	United States, Dallas (Texas)  
isp:	AS16509 Amazon.com, Inc. » Amazon.com, Inc. » AWS CloudFront (GLOBAL) 386.995 ms
route:	3.168.0.0/21, AMAZON-CF - Amazon.com, Inc., US (Dallas) ... 
reg:	3.128.0.0/9, US, ARIN, 2018-06-25
asn:	AS16509 - AMAZON-02 Amazon.com Inc., US
addr:	  1918 8th Ave SEATTLE WA 98101-1244 US
online:	  1.983 » latency: 135 ms (135ms) 

see also:
   3.128.0.0/10     AS16509  AT-88-Z Amazon Technologies Inc., US