Gateway Endpoint vs Interface Endpoint in AWS: Key Differences and Usage

In AWS, a Gateway Endpoint connects your VPC privately to supported AWS services like S3 and DynamoDB using route tables, while an Interface Endpoint uses elastic network interfaces with private IPs to connect to many AWS services and third-party APIs. Gateway endpoints are simpler and free, but interface endpoints offer broader service support and more control.

Quick Comparison

This table summarizes the main differences between Gateway and Interface endpoints in AWS.

Feature	Gateway Endpoint	Interface Endpoint
Connection Type	Uses route tables to direct traffic	Uses elastic network interfaces (ENIs) with private IPs
Supported Services	Only Amazon S3 and DynamoDB	Many AWS services and some third-party services
Cost	No additional cost	Charged per hour and data processed
Security Controls	Controlled via VPC route tables and policies	Supports security groups for fine-grained control
Use Case	Simple, high-throughput access to S3/DynamoDB	Private access to a wide range of AWS services
Availability	Regional, highly available	Regional, highly available

Key Differences

Gateway Endpoints are designed specifically for Amazon S3 and DynamoDB. They work by adding entries to your VPC's route tables, so traffic to these services is routed privately without leaving the AWS network. This makes them simple to set up and cost-effective since there are no hourly or data processing charges.

On the other hand, Interface Endpoints create elastic network interfaces (ENIs) with private IP addresses inside your VPC. These ENIs act like network adapters that connect your VPC privately to many AWS services beyond S3 and DynamoDB, including services like EC2 API, SNS, and third-party services. Interface endpoints allow you to use security groups to control traffic, giving you more granular security control.

While gateway endpoints are free and straightforward, interface endpoints incur hourly and data processing costs. They also provide more flexibility and security features, making them suitable when you need private connectivity to a broader set of services or want to control access tightly.

Gateway Endpoint Code Example

This example shows how to create a Gateway Endpoint for Amazon S3 using AWS CloudFormation.

yaml

Resources:
  S3GatewayEndpoint:
    Type: AWS::EC2::VPCEndpoint
    Properties:
      VpcId: vpc-123abc
      ServiceName: !Sub com.amazonaws.${AWS::Region}.s3
      RouteTableIds:
        - rtb-123abc
        - rtb-456def
      VpcEndpointType: Gateway

Output

Creates a gateway endpoint in the specified VPC that routes S3 traffic privately through the listed route tables.

Interface Endpoint Equivalent

This example shows how to create an Interface Endpoint for Amazon EC2 API using AWS CloudFormation.

yaml

Resources:
  EC2InterfaceEndpoint:
    Type: AWS::EC2::VPCEndpoint
    Properties:
      VpcId: vpc-123abc
      ServiceName: !Sub com.amazonaws.${AWS::Region}.ec2
      SubnetIds:
        - subnet-123abc
        - subnet-456def
      SecurityGroupIds:
        - sg-123abc
      VpcEndpointType: Interface

Output

Creates an interface endpoint in the specified VPC subnets with security group controls for private EC2 API access.

When to Use Which

Choose a Gateway Endpoint when you need simple, cost-free private access to Amazon S3 or DynamoDB from your VPC. It is ideal for high-throughput workloads that require minimal setup and no additional cost.

Choose an Interface Endpoint when you need private connectivity to AWS services other than S3 and DynamoDB, or when you want to apply fine-grained security controls using security groups. It is best for accessing a wide range of AWS or third-party services privately with more control, even if it incurs additional cost.

Key Takeaways

Gateway endpoints provide free, simple private access only to S3 and DynamoDB using route tables.

Interface endpoints use ENIs with private IPs to connect to many AWS services and support security groups.

Use gateway endpoints for cost-effective, high-throughput S3/DynamoDB access.

Use interface endpoints for private access to other AWS services or when fine-grained security is needed.

Interface endpoints incur hourly and data processing costs, unlike gateway endpoints.