Transit Gateway and VPC Transit

AWS provides a service called Transit Gateway that simplifies the process of connecting multiple Virtual Private Clouds (VPCs) and establishing transit routing between them. With Transit Gateway, you can build a hub-and-spoke architecture for your VPCs, making it easier to manage and scale your network infrastructure.

How Transit Gateway Works

Transit Gateway acts as a central hub that allows VPCs to connect and communicate with each other. Instead of establishing separate connectivity between each pair of VPCs, you can create a single Transit Gateway and connect all the VPCs to it. This simplifies network management and reduces the number of connections required.

Here's an example of how Transit Gateway can be used to connect two VPCs:

1// Create and configure a Transit Gateway
2TransitGateway transitGateway = new TransitGateway();
3transitGateway.setName("MyTransitGateway");
4
5// Create VPCs
6Vpc vpc1 = new Vpc();
7vpc1.setName("VPC1");
8Vpc vpc2 = new Vpc();
9vpc2.setName("VPC2");
10
11// Connect VPCs to Transit Gateway
12transitGateway.connectVpc(vpc1);
13transitGateway.connectVpc(vpc2);
14
15// Configure route tables
16RouteTable vpc1RouteTable = new RouteTable();
17vpc1RouteTable.setName("VPC1RouteTable");
18vpc1RouteTable.addRoute("10.0.0.0/16", "Local");
19vpc1RouteTable.addRoute("172.16.0.0/16", "TransitGateway");
20vpc1.setRouteTable(vpc1RouteTable);
21
22RouteTable vpc2RouteTable = new RouteTable();
23vpc2RouteTable.setName("VPC2RouteTable");
24vpc2RouteTable.addRoute("10.0.0.0/16", "Local");
25vpc2RouteTable.addRoute("172.16.0.0/16", "TransitGateway");
26vpc2.setRouteTable(vpc2RouteTable);
27
28// Test connectivity
29vpc1.ping(vpc2);

In this example, we create a Transit Gateway named "MyTransitGateway" and connect two VPCs, "VPC1" and "VPC2", to it. Each VPC has its own route table, which is configured to route traffic destined for the other VPC through the Transit Gateway.

With this setup, instances in "VPC1" can communicate with instances in "VPC2" using private IP addresses. The Transit Gateway handles the underlying network routing between the VPCs.

Transit Gateway provides a scalable and highly available solution for connecting VPCs, making it easier to build and manage complex network architectures.

xxxxxxxxxx

}

class Main {

  public static void main(String[] args) {

    // Replace with your Java logic here

    // Create and configure a Transit Gateway

    TransitGateway transitGateway = new TransitGateway();

    transitGateway.setName("MyTransitGateway");

​

    // Create VPCs

    Vpc vpc1 = new Vpc();

    vpc1.setName("VPC1");

    Vpc vpc2 = new Vpc();

    vpc2.setName("VPC2");

​

    // Connect VPCs to Transit Gateway

    transitGateway.connectVpc(vpc1);

    transitGateway.connectVpc(vpc2);

​

    // Configure route tables

    RouteTable vpc1RouteTable = new RouteTable();

    vpc1RouteTable.setName("VPC1RouteTable");

    vpc1RouteTable.addRoute("10.0.0.0/16", "Local");

    vpc1RouteTable.addRoute("172.16.0.0/16", "TransitGateway");

    vpc1.setRouteTable(vpc1RouteTable);

​

    RouteTable vpc2RouteTable = new RouteTable();

    vpc2RouteTable.setName("VPC2RouteTable");

    vpc2RouteTable.addRoute("10.0.0.0/16", "Local");

    vpc2RouteTable.addRoute("172.16.0.0/16", "TransitGateway");

    vpc2.setRouteTable(vpc2RouteTable);