16.182.39.109
s3-website-us-east-1.amazonaws.com
52.216.221.221
s3-website-us-east-1.amazonaws.com
52.216.248.155
s3-website-us-east-1.amazonaws.com
52.216.26.11
s3-website-us-east-1.amazonaws.com
52.216.58.253
s3-website-us-east-1.amazonaws.com
52.217.203.29
s3-website-us-east-1.amazonaws.com
54.231.139.237
s3-website-us-east-1.amazonaws.com
54.231.169.125
s3-website-us-east-1.amazonaws.com

usb-smtp-inbound-1.mimecast.com.
usb-smtp-inbound-2.mimecast.com.