A company plans to build a custom natural language processing (NLP) model to classify and prioritize user feedback. The company hosts the data and all machine learning (ML) infrastructure in the AWS C

Creating a VPC interface endpoint (powered by AWS PrivateLink) for SageMaker Notebooks establishes a private connection directly from the VPC to the SageMaker service. This ensures all traffic remains within the AWS internal network from the VPN-connected on-premises environment, fulfilling the private access requirement with minimal setup effort.

A bastion host in a public subnet would require traffic to traverse the public internet to reach the bastion host, violating the strict requirement for private network access.

Using a bastion host in a private subnet with a NAT gateway implies public internet access for outbound traffic or a more complex routing setup, adding significant development effort and potentially still routing through public IPs for the SageMaker endpoint if not using PrivateLink.

A NAT gateway enables instances in private subnets to initiate public internet access; it does not provide private, direct access to SageMaker notebooks from on-premises without routing through the public internet for the SageMaker service endpoint itself.