# Transit gateway attachments to a Direct Connect gateway in Amazon Transit Gateway
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Attach a transit gateway to a Direct Connect gateway using a transit virtual interface. This configuration offers the following benefits. You can:
+ Manage a single connection for multiple VPCs or VPNs that are in the same Region.
+ Advertise prefixes from on-premises to Amazon and from Amazon to on-premises.

The following diagram illustrates how the Direct Connect gateway enables you to create a single connection to your Direct Connect connection that all of your VPCs can use.

![Direct Connect Gateway Connected to Transit Gateway](http://docs.amazonaws.cn/en_us/vpc/latest/tgw/images/direct-connect-tgw.png)


The solution involves the following components:
+ A transit gateway.
+ A Direct Connect gateway.
+ An association between the Direct Connect gateway and the transit gateway.
+ A transit virtual interface that is attached to the Direct Connect gateway.

For information about configuring Direct Connect gateways with transit gateways, see [Transit gateway associations](https://docs.amazonaws.cn/directconnect/latest/UserGuide/direct-connect-transit-gateways.html) in the *Amazon Direct Connect User Guide*.