Secure way to give internet access to your private subnet in AWS without Internet Gateway (IGW)

Understanding of Public and Private Subnets:

Amazon Virtual Private Cloud (VPC) enables you to create isolated, private networks within the AWS cloud and further segment your network into public and private subnets.

Public Subnets:

Public subnets have a gateway connected to them, enabling direct communication with the public internet. Typically, a NAT gateway translates private IP addresses to public IP addresses, enabling outbound traffic from the private subnet to the internet.

Public subnets are commonly utilized for web servers, load balancers, and other services that require accessibility from the public internet.

Private Subnets:

Private subnets do not have a gateway attached to them, which prevents direct communication with the public internet. They are primarily used for internal communication within the VPC or with on-premises networks.

Private subnets are optimal for databases, application servers, and other resources that should not be directly accessible from the public internet.

For instance, if the application is located in a private subnet and needs to access other resources over the internet, VPC endpoints can be utilized. 

Types of AWS VPC endpoints:

AWS VPC Endpoints create a private connection between Amazon Virtual Private Cloud (VPC) and other AWS services or other on-premises data centers. This removes the need to expose your VPC to the public internet, which improves security and reduces latency.

Gateway Endpoints:

• Connect your VPC to specific AWS services like S3, DynamoDB, and Kinesis Data Streams.

• All traffic is routed through AWS infrastructure, ensuring a private connection.

• This is ideal for accessing services that do not require public internet access.

Interface Endpoints:

• Create a private IP address within your VPC for accessing specific AWS services or your on-premises network.

• Traffic is routed through a network interface within your VPC, which provides more detailed control.

• Suitable for accessing services that require a private IP address or for connecting to on-premises networks.

AWS VPC endpoints allow for a private and secure connection to services outside your VPC without requiring internet or internet gateways. Connectivity through the internet gateway is over the public internet, which is not secure or private. This is achievable with Amazon's virtual private cloud.