Simplifying Multi-VPC Connectivity with AWS Transit Gateway
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Multi VPC Connectivity
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- Transit Gateways can be thought of as a Big Pipe which can be further divided into smaller pipes using Route Tables.
- Route Tables further can be divided into smaller pipes which route traffic based on target CIDR Blocks.
- Input to and Output from transit gateway happens via Transit Gateway Attachments. Transit Gateway Attachments are bound to a VPC.
- To establish the Inbound connectivity to a Transit Gateway, TGW Attachment needs to create association with a specific Route Table on Transit Gateway.
- Route Table in the Transit Gateway specifies the Outbound connectivity with a TGW Attachment based on the CIDR block.