What is a VPC Endpoint?

A VPC endpoint is a private connection between a Virtual Private Cloud (VPC) and supported AWS services or customer/service provider networks. Instead of routing traffic over the public internet, a VPC endpoint uses the AWS network to keep data within the cloud’s private space. This approach improves security, reduces exposure to external threats, and often decreases latency for services your workloads rely on.

In AWS, there are two main categories of VPC endpoints: Gateway endpoints and Interface endpoints. Each type serves different use cases and supports different services. Understanding these options helps you design a robust network strategy that aligns with security and compliance goals.

Types of VPC Endpoints

The two primary endpoint types you’ll encounter are:

• Gateway Endpoints – These endpoints provide private access to specific AWS services, notably S3 and DynamoDB, by extending your VPC route tables. They do not create an elastic network interface (ENI) in your subnets and typically incur no per-endpoint hourly charge. Traffic to the connected service stays within the AWS network and never traverses the public internet.
• Interface Endpoints – Built on AWS PrivateLink, these endpoints use elastic network interfaces (ENIs) in your subnets to privately access a broad range of AWS services and many third‑party services. Interface endpoints are more flexible and can connect to many services, but they do involve hourly charges for the endpoint and data processing charges for traffic that passes through PrivateLink.

When planning connectivity to services outside AWS, you might also encounter PrivateLink concepts that underpin interface endpoints. PrivateLink makes it possible to expose services securely and privately within your VPC or across VPCs, while still controlling access through policies.

How VPC Endpoints Work

The magic behind a VPC endpoint is how it integrates with your VPC’s routing. For gateway endpoints, you add a route in the VPC’s route table directing traffic destined for the chosen AWS service to the endpoint. For interface endpoints, the AWS service is accessed via an ENI that exists in your subnet, and the endpoint’s private DNS names are resolved to the private IPs inside your VPC.

A key feature is the endpoint policy. This policy controls which principals (users or roles) can access the service through the endpoint and what actions are allowed. For broad use, you might apply a permissive policy during testing and then tighten it to the least privilege required for your workloads.

DNS plays a critical role. With Private DNS enabled for an interface endpoint, your existing domain names for the AWS service resolve to private addresses inside your VPC. This keeps traffic fully within the private network and avoids public DNS resolution.

Use Cases for VPC Endpoints

• Private access to S3 or DynamoDB: Use gateway endpoints to securely read and write data to S3 or DynamoDB without exposing traffic to the internet.
• Private access to AWS services and partner services: Interface endpoints let you reach services like AWS Systems Manager, Secrets Manager, or third‑party services via PrivateLink without leaving the VPC.
• Hybrid and multi‑VPC architectures: Centralize access control and monitoring by using endpoints to connect multiple VPCs to shared services.
• Compliance and data residency: Keeping data traffic on the private AWS network helps meet regulatory requirements that restrict internet exposure.
• Secure egress control: Combine endpoints with security groups, IAM, and endpoint policies to tightly control how services are accessed from private subnets.

Choosing the Right Type for Your Scenario

When deciding between gateway and interface endpoints, consider the following:

• Do you need private access to S3 or DynamoDB specifically? Gateway endpoints are simple, cost‑effective, and ideal for these services.
• Do you require access to a broader set of AWS services or to third‑party services through PrivateLink? Interface endpoints offer flexibility and private connectivity via ENIs.
• Is it important to avoid any traffic going to the public internet? Both endpoint types help achieving this, but interface endpoints provide more granular control for non‑AWS services.
• What are your cost considerations? Interface endpoints incur hourly charges and data processing fees, while gateway endpoints typically have no per‑endpoint hourly charge but still incur standard data transfer costs for traffic to S3 or DynamoDB.

Best Practices for VPC Endpoints

• : Start with a narrowly scoped policy and expand only as needed by your workloads.
• : This ensures private resolution for AWS service endpoints, keeping traffic within the VPC.
• : Group resources and endpoints by team or environment (dev, test, prod) to simplify management and auditing.
• : For interface endpoints, use security groups to control inbound traffic to the ENIs.
• : Enable VPC flow logs and CloudWatch metrics to track endpoint usage and troubleshoot issues.
• : Regularly evaluate endpoint types and data transfer patterns to optimize cost.

Configuration Snapshot: How to Set Up a VPC Endpoint

This high‑level walkthrough shows typical steps for a gateway or interface endpoint. Replace placeholders with your actual IDs and service names.

1. Identify the VPC and subnets where you want the endpoint to live, and determine the service you need to reach.
2. Choose the endpoint type: gateway for S3/DynamoDB or interface for other services.
3. Create the endpoint and apply an endpoint policy to control access.
4. For interface endpoints, attach to one or more subnets and assign security groups to the ENIs.
5. Update route tables (gateway endpoints) or enable Private DNS (interface endpoints) as needed.
6. Test connectivity from a source instance or service to verify private access works as expected.

Example (AWS CLI):

aws ec2 create-vpc-endpoint \
  --vpc-id vpc-0example \
  --service-name com.amazonaws.us-east-1.s3 \
  --route-table-ids rtb-0123456789abcdef \
  --endpoint-type Gateway

Another example for an interface endpoint:

aws ec2 create-vpc-endpoint \
  --vpc-id vpc-0example \
  --service-name com.amazonaws.us-east-1.ssm \
  --subnet-ids subnet-11111111 subnet-22222222 \
  --security-group-ids sg-0abcd1234ef567890 \
  --endpoint-type Interface

Security and Compliance Considerations

VPC endpoints play a meaningful role in security architectures. They help you keep traffic within the AWS network, reduce exposure to the public internet, and enforce access controls via endpoint policies and IAM. When combined with other controls—such as dedicated IAM roles, VPC security groups, and resource policies—you can create a layered defense that aligns with governance requirements.

Remember to review service‑specific considerations. Some AWS services may require additional configuration for PrivateLink, supported regions, or endpoint policy nuances. Regular audits and testing help ensure your endpoints meet evolving security and compliance needs.

Conclusion

VPC endpoints offer a practical path to private, reliable, and scalable connectivity within AWS. By choosing the right endpoint type, applying precise policies, and following best practices for DNS, routing, and monitoring, you can simplify access to S3, DynamoDB, and other services while maintaining strong security and predictable costs.

Whether you are consolidating egress control in a single VPC or enabling private access for a multi‑VPC architecture, VPC endpoints are a foundational tool in modern AWS networking. Start with a clear understanding of your use cases, evaluate the cost implications of gateway versus interface endpoints, and iteratively refine your configuration to balance performance, security, and operational efficiency.