Every Amazon Neptune DB Cluster resides in an Amazon VPC - Amazon Neptune
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Every Amazon Neptune DB Cluster resides in an Amazon VPC

An Amazon Neptune DB cluster can only be created in an Amazon Virtual Private Cloud (Amazon VPC), and its endpoints are only accessible within that VPC, usually from an Amazon Elastic Compute Cloud (Amazon EC2) instance running in that VPC.

You can secure your Neptune data by limiting access to the VPC where your Neptune DB cluster is located, as described in Connecting to your Amazon Neptune graph.