Amazon DynamoDB now supports resource-based policies to help you simplify access control for your DynamoDB resources. With resource-based policies, you can specify the Identity and Access Management (IAM) principals that have access to a resource and what actions they can perform on it. You can attach a resource-based policy to a DynamoDB table or a stream. The resource-based policy that you attach to a table can include access permissions to its indexes. The resource-based policy that you attach to a stream can include access permissions to the stream. With resource-based policies, you can also simplify cross-account access control for sharing resources with IAM principals of different AWS accounts.
Source:: Amazon AWS