Welcome everyone! Today we're diving deep into AWS Direct Connect with Transit Gateway - one of the most powerful networking combinations in AWS.
I've been working with Direct Connect for over 5 years, and I can tell you that the introduction of Transit Gateway has completely transformed how we design enterprise network architectures.
By the end of this presentation, you'll understand exactly when to use each VIF type, how to configure them properly, and most importantly - how to avoid the common pitfalls I've seen teams struggle with.
Before Transit Gateway, connecting on-premises to multiple VPCs was a nightmare. I remember one client who had 15 VPCs and needed individual VPN connections or Direct Connect attachments to each one.
This diagram shows the old way - notice how complex it gets with just 3 VPCs. Imagine scaling this to 50 or 100 VPCs!
Each connection required separate BGP sessions, individual route management, and worst of all - no inter-VPC communication without additional complexity.
Now look at this architecture - this is the power of Transit Gateway! One connection from on-premises reaches all your VPCs through a single hub.
What makes this beautiful is that Transit Gateway acts as a cloud router. Your on-premises network sees just one BGP peer, but it can reach workloads across multiple VPCs and even multiple regions.
I've implemented this for clients who went from managing 20+ BGP sessions down to just 2 or 3. The operational simplicity is game-changing.
Here's where it gets interesting - AWS gives us three different types of Virtual Interfaces, and choosing the wrong one can limit your architecture for years.
Private VIF is the traditional approach - it connects to individual VPCs through a Virtual Gateway. It's like having a dedicated lane on the highway to one destination.
Public VIF is special - it only connects to AWS public services like S3 and DynamoDB. Many people don't realize this VIF type exists, but it's crucial for high-bandwidth access to AWS services.
Transit VIF is the newcomer and game-changer - it's specifically designed for Transit Gateway and supports up to 100 Gbps per VIF. This is where the future is headed.
This is probably the most common question I get: "Do I need a Virtual Gateway if I'm using Transit Gateway?" The answer is a definitive NO for most modern use cases.
I see this decision point with every client. The traditional path with VGW is simpler initially, but it doesn't scale. If you have any chance of adding more VPCs - and let's be honest, most organizations do - go with Transit Gateway from day one.
The cost difference is minimal, but the architectural flexibility you gain is enormous. I've never had a client regret choosing Transit Gateway over VGW.