Introduction to AWS Transit Gateway
By Pooja | 3rd July 2025
Introduction
As businesses adopt cloud computing, the need to interconnect multiple Virtual Private Clouds (VPCs) and on-premises networks becomes essential. Traditionally, organizations relied on complex VPC peering connections or VPNs to achieve this. However, these solutions become hard to manage and scale as the number of connections increases. AWS Transit Gateway is a cloud-native service introduced by Amazon Web Services that simplifies this challenge by acting as a central hub that connects all VPCs and on-premises networks using a hub-and-spoke model. This not only reduces the complexity but also enhances performance and manageability.
Features and Advantages
You may also be interested in our blog on 🔹Centralized Connectivity
Instead of setting up peering connections between each VPC individually, AWS Transit Gateway provides a central router for all network traffic. Each VPC, site-to-site VPN, or AWS Direct Connect connection is attached to the Transit Gateway. This drastically reduces the number of network connections required and makes your architecture more organized and easy to scale.
🔹 Simplified Network Management
With Transit Gateway, route tables are defined and associated with attachments (VPCs, VPNs, etc.), which makes routing more manageable. You no longer need to manually update each individual VPC route table. Changes can be made centrally, and policies can be applied consistently across environments. This also improves visibility and control over network traffic.
🔹 Scalability and High Availability
Transit Gateway is designed for scale. It can support thousands of VPCs and connections without performance degradation. AWS ensures that TGW is highly available and redundant, operating across multiple Availability Zones (AZs) to provide fault tolerance and uninterrupted service even during outages.
🔹 Secure and Isolated Networking
Each connection (or “attachment”) to the Transit Gateway can have its own route table, enabling traffic segmentation and isolation. You can create specific rules to control which VPCs can talk to each other and what data flows through. Integration with AWS Resource Access Manager (RAM) allows organizations to share a Transit Gateway across multiple AWS accounts, increasing operational efficiency without compromising on security.
🔹 Cost-Effective Architecture
With Transit Gateway, businesses can optimize their network and reduce the overhead associated with maintaining multiple VPNs or VPC peering relationships. Data transferred between VPCs over TGW can be more economical than traditional peering in large-scale setups. It also saves administrative time and effort, further reducing operational costs.
🔹 Interoperability with AWS Services
Transit Gateway seamlessly integrates with services like AWS Direct Connect, AWS VPN, AWS Network Firewall, and Amazon CloudWatch. This ensures that businesses can monitor, secure, and expand their networks with minimal additional setup. Additionally, it supports multicast traffic, which is useful for applications such as video conferencing or stock trading platforms.
You may also be interested in our blog on How Is a VPC Different from Traditional On-Premise Networking?
Conclusion
In today’s dynamic cloud environments, managing a growing number of networks requires a robust and centralized approach. AWS Transit Gateway offers a reliable, scalable, and cost-efficient way to interconnect VPCs, on-premises networks, and AWS services. By consolidating network traffic through a central gateway, organizations gain greater control, security, and flexibility, enabling them to focus on innovation rather than infrastructure complexity. Whether you’re a small startup expanding across regions or an enterprise managing global infrastructure, Transit Gateway provides the backbone for building efficient and resilient cloud networking solutions.