---
type: resource-type
title: TransitGateway
description: aws resource type AWS::EC2::TransitGateway
name: TransitGateway
lexicon: aws
resource_type: AWS::EC2::TransitGateway
---
`AWS::EC2::TransitGateway`, a resource type of the aws lexicon.

## Properties

- `AmazonSideAsn` (`number`, optional)
- `AssociationDefaultRouteTableId` (`string`, optional)
- `AutoAcceptSharedAttachments` (`string`, optional)
- `DefaultRouteTableAssociation` (`string`, optional)
- `DefaultRouteTablePropagation` (`string`, optional)
- `Description` (`string`, optional)
- `DnsSupport` (`string`, optional)
- `EncryptionSupport` (`"disable" | "enable"`, optional)
- `EncryptionSupportState` (`string`, optional)
- `Id` (`string`, optional)
- `MulticastSupport` (`string`, optional)
- `PropagationDefaultRouteTableId` (`string`, optional)
- `SecurityGroupReferencingSupport` (`string`, optional)
- `Tags` (`TransitGateway_Tag[]`, optional)
- `TransitGatewayArn` (`string`, optional)
- `TransitGatewayCidrBlocks` (`string[]`, optional)
- `VpnEcmpSupport` (`string`, optional)

## Attributes

- `EncryptionSupportState`
- `Id`
- `TransitGatewayArn`

## Governed by

- [WAW064](/rules/WAW064.md): Transit Gateway route table declares a Blackhole route — confirm the traffic drop is intentional, not an accident
- [WAW065](/rules/WAW065.md): Transit Gateway route table has associations but no propagations, or an attachment wired into no route table
- [WAW068](/rules/WAW068.md): VPN Gateway or Transit Gateway has only one attached VPN Connection — no redundant path for hybrid connectivity