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The auditing configuration created as part of our Standard AWS Account Configuration includes setting up auditing in all AWS regions. This is to log activity in an AWS account targeting other AWS regions. These costs should be minimal because most folks aren't using regions across the globe. However, it is important that the auditing configuration is in place globally to ensure that any malfeasance in other regions is logged.
What is the AWS Data Egress Waiver?
AWS offers a Data Egress Waiver that mostly eliminates Data Transfer charges for Cornell. See the AWS blog post about it for more details.
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