A VPC endpoint enables private connections between your VPC and supported AWS services without requiring an internet gateway, NAT device, VPN connection, or Direct Connect connection. Instances in your VPC do not require public IP addresses to communicate with resources in the service. Traffic between your VPC and the other service does not leave the AWS network.
Endpoints are virtual devices. They are horizontally scaled, redundant, and highly available VPC components. They permit communication between instances in your VPC and services without imposing availability risks or bandwidth constraints on your network traffic.
Types of VPC endpoints
GATEWAY ENDPOINT
Specify a gateway endpoint as a route target in your route table. A gateway endpoint is meant for traffic destined to Amazon S3, or Amazon DynamoDB and remains inside the AWS network.
instance A in the public subnet communicates with Amazon S3 via an internet gateway. Instance A has a route to local destinations in the VPC. Instance B communicates with an Amazon S3 bucket and an Amazon DynamoDB table using unique gateway endpoints. The diagram shows an example of a private route table. The private route table directs your Amazon S3 and DynamoDB requests through each gateway endpoint using routes. The route table uses a prefix list to target the specific Region for each service.
INTERFACE ENDPOINT
With an interface VPC endpoint (interface endpoint), you can privately connect your VPC to services as if they were in your VPC. When the interface endpoint is created, traffic is directed to the new endpoint without changes to any route tables in your VPC.
For example, a Region is shown with Systems Manager outside of the example VPC. The example VPC has a public and private subnet with an Amazon Elastic Compute Cloud (Amazon EC2) instance in each. Systems Manager traffic sent to ssm.region.amazonaws.com is sent to an elastic network interface in the private subnet.
Gateway VPC endpoints and interface VPC endpoints help you access services over the AWS backbone.
A gateway VPC endpoint (gateway endpoint) is a gateway that you specify as a target for a route in your route table for traffic destined for a supported AWS service. The following AWS services are supported: Amazon S3 and Amazon DynamoDB.
An interface VPC endpoint (interface endpoint) is an elastic network interface with a private IP address from the IP address range of your subnet. The network interface serves as an entry point for traffic destined to a supported service. AWS PrivateLink powers interface endpoints and it avoids exposing traffic to the public internet.
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Osama
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