# TransitGatewayOptions


Describes the options for a transit gateway.

## Contents


 ** amazonSideAsn **   
A private Autonomous System Number (ASN) for the Amazon side of a BGP session. The range is 64512 to 65534 for 16-bit ASNs and 4200000000 to 4294967294 for 32-bit ASNs.  
Type: Long  
Required: No

 ** associationDefaultRouteTableId **   
The ID of the default association route table.  
Type: String  
Required: No

 ** autoAcceptSharedAttachments **   
Indicates whether attachment requests are automatically accepted.  
Type: String  
Valid Values: `enable | disable`   
Required: No

 ** defaultRouteTableAssociation **   
Indicates whether resource attachments are automatically associated with the default association route table. Enabled by default. Either `defaultRouteTableAssociation` or `defaultRouteTablePropagation` must be set to `enable` for AWS Transit Gateway to create the default transit gateway route table.  
Type: String  
Valid Values: `enable | disable`   
Required: No

 ** defaultRouteTablePropagation **   
Indicates whether resource attachments automatically propagate routes to the default propagation route table. Enabled by default. If `defaultRouteTablePropagation` is set to `enable`, AWS Transit Gateway creates the default transit gateway route table.  
Type: String  
Valid Values: `enable | disable`   
Required: No

 ** dnsSupport **   
Indicates whether DNS support is enabled.  
Type: String  
Valid Values: `enable | disable`   
Required: No

 ** encryptionSupport **   
Defines if the Transit Gateway supports VPC Encryption Control.  
Type: [EncryptionSupport](API_EncryptionSupport.md) object  
Required: No

 ** multicastSupport **   
Indicates whether multicast is enabled on the transit gateway  
Type: String  
Valid Values: `enable | disable`   
Required: No

 ** propagationDefaultRouteTableId **   
The ID of the default propagation route table.  
Type: String  
Required: No

 ** securityGroupReferencingSupport **   
Enables you to reference a security group across VPCs attached to a transit gateway to simplify security group management.   
This option is disabled by default.  
Type: String  
Valid Values: `enable | disable`   
Required: No

 ** TransitGatewayCidrBlocks.N **   
The transit gateway CIDR blocks.  
Type: Array of strings  
Required: No

 ** vpnEcmpSupport **   
Indicates whether Equal Cost Multipath Protocol support is enabled.  
Type: String  
Valid Values: `enable | disable`   
Required: No

## See Also


For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/ec2-2016-11-15/TransitGatewayOptions) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/ec2-2016-11-15/TransitGatewayOptions) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/ec2-2016-11-15/TransitGatewayOptions)