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VPC Endpoints & AWS PrivateLink

Private paths from a VPC to AWS and endpoint services: gateway endpoints, interface endpoints, PrivateLink mechanics, DNS behavior and when a NAT or internet gateway is unnecessary.

CLF-C02AIP-C01

Visual overview

PRIVATE SERVICE ACCESSChoose the endpoint mechanism from the service and the location of the consumer
GATEWAY ENDPOINTS3 / DynamoDBRoute-table target · no PrivateLink · no endpoint charge
INTERFACE ENDPOINTPrivate IPs in selected subnetsEndpoint ENIs · security groups · private DNS
PRIVATELINKService-specific connectivityPrivate service access without broad VPC-to-VPC routing
VPC endpoints can keep supported service traffic on private connectivity without requiring a NAT gateway or internet gateway for that destination.
AWS SERVICE MAPPrivate access to a specific service

PrivateLink interface endpoints provide private service entry points without broad VPC-to-VPC routing.

Consumer VPCPrivate workload
AWS PrivateLinkInterface endpoint
AWS servicePrivate destination
EXAM-RELEVANT MECHANICS

Technical reference

Endpoint type changes packet mechanics and scope.

Gateway endpointS3 / DynamoDB

A route-table target for those services; it does not use AWS PrivateLink.

Interface endpointENIs + private IPs

Creates endpoint network interfaces in selected subnets and uses PrivateLink.

Private DNSService name → endpoint

Supported service names can resolve to interface-endpoint private addresses when private DNS is enabled.

Internet pathNot required

Supported endpoint traffic does not need an IGW or NAT device for that destination.

Private service access without traversing the public internet

A VPC endpoint lets resources in a VPC reach supported AWS services or endpoint services using private connectivity without requiring an internet gateway or NAT device for that service path. This can reduce public exposure and simplify architectures in which workloads should remain on private addressing. Endpoint type matters because gateway and interface endpoints have different network mechanics, supported targets and pricing models.

An endpoint does not bypass authorization. The caller still needs the service-level permissions required for the requested API operation, and endpoint policies can add another authorization boundary where supported. Route tables, security groups and DNS behavior also differ by endpoint type, so 'we created an endpoint' is not sufficient troubleshooting evidence by itself.

Gateway endpoints: S3 and DynamoDB through routing

Gateway endpoints provide private access to Amazon S3 and DynamoDB from a VPC. You select route tables, and AWS adds service prefix-list routes whose target is the gateway endpoint. Traffic matching those service destinations takes the endpoint route rather than requiring an internet or NAT path. AWS documents no additional charge for gateway endpoints themselves, making them an important architectural option for private S3/DynamoDB traffic.

Gateway endpoints have scope limitations. For example, S3 gateway endpoint access is designed for resources whose traffic can use the associated VPC route table; accessing privately from on-premises networks, peered VPCs or some transit patterns can require an interface endpoint instead. The architecture should choose the endpoint type from the location of clients and service support, not simply from cost.

Key takeaways

  1. 01

    VPC endpoints create private service paths that do not require NAT or an internet gateway for that supported destination.

  2. 02

    Gateway endpoints serve S3 and DynamoDB using route-table entries and do not use AWS PrivateLink.

  3. 03

    Interface endpoints use private IP network interfaces and AWS PrivateLink; security groups and private DNS are important controls.

  4. 04

    PrivateLink can expose a specific service privately without providing general routed connectivity between VPCs.

Official AWS sources

Use these primary AWS resources for the source material behind this article and for deeper reference.