Traffic between an Amazon VPC and AWS Transit Gateway remains on AWS's private network and it is not exposed to the public internet. This reduces threat vectors such as distributed denial of service (DDoS) attacks and common exploits, such as SQL injection, cross-site scripting, cross-site request forgery, or abuse of broken authentication code. Transit Gateway inter-region peering also encrypts inter-region traffic with no single point of failure or bandwidth bottleneck.

Simplify how you interconnect all of your of VPCs, across thousands of AWS accounts and into your on-premises networks. You can easily and quickly connect into a single centrally-managed gateway, rapidly growing the size of your network. With Transit Gateway inter-region peering, you can easily connect Transit Gateway and its attachments, such as Amazon VPC, AWS Direct Connect, or AWS Site-to-Site VPNs, across multiple AWS regions.

AWS Transit Gateway multicast is the only cloud-based multicast solution, to quickly distribute the same content to multiple, specific destinations. Transit Gateway multicast eliminates the need for on-premises multicast networks, enabling you to send multicast data straight from multicast applications in AWS. It reduces the bandwidth need across the network for high-throughput applications such as video conferencing, media, or teleconferencing. With less congestion from needing less bandwidth, multicast helps end subscribers get the information quickly.

Expand your network quickly to get the bandwidth you need to transfer large amounts of data for your applications or to enable your migration to the cloud. Quickly add Amazon VPCs to your network without having to provision additional connections from your on-premises networks to AWS. 

With AWS Transit Gateway network manager, you can easily monitor all of your Amazon VPCs and edge connections in a single console with centralized monitoring and controls. Your teams can also quickly identify issues and react to events on your network.

Build applications that span thousands of Amazon VPCs without the operational burden of managing a distributed network. Connecting and managing hundreds or thousands of VPCs via peering requires massive route tables which is difficult to deploy, manage and can be error prone. Now, there are far fewer routes to configure since you only configure the route to AWS Transit Gateway rather than to each VPC. 

As your network grows to support more users in different parts of the world, you will need to scale AWS services within your network. With AWS Transit Gateway, you can easily share AWS resources and services, such as DNS, Active Directory, and IPS/IDS, across AWS Regions, in all of your Amazon VPCs, or replicate data for geographic redundancy.

Peak demand is often unpredictable. You need to be able to easily and quickly grow network capacity. With AWS Transit Gateway you can easily add more Amazon VPCs and AWS accounts to support increased demands on your workloads.

With Transit Gateway multicast, for the first time in the cloud, you can host multicast applications without redesigning the application, or tweaking your on-premises network to share multicast traffic with users.

You can now build multicast applications in the cloud that can scale up and down based on demand, and you don’t have to buy and maintain custom hardware to support your peak application loads.