Transit Gateway (TGW) - Test

Information related to Transit Gateway build

Default Quotas

Per: https://docs.aws.amazon.com/vpc/latest/tgw/transit-gateway-quotas.html

* Security Group for an EC2 instance needs to also include the CIDR block of the VPC from which you're trying to allow access to

* VPC subnet route table must include a route which connects a certain CIDR block to a TGW

* VPC subnet needs to have a route for IGW to allow access from outside addresses

Pricing

https://aws.amazon.com/transit-gateway/pricing/

A transit gateway by itself does not cost money and is not associated with any VPC.
There is a static cost that comes from an hourly rate for an attachment to the TGW:
- Price per AWS Transit Gateway attachment ($): $0.05/per hour
- Price per GB of data processed ($): $0.02
AWS Site-to-Site VPN connection pricing still applies in addition to AWS Transit Gateway VPN attachment pricing:
- $0.05 per Site-to-Site VPN connection per hour

A TGW attachment in an account outside of the one where the TGW is hosted, will be subject to charges for the TGW attachment, not the account with the TGW.

Examples (excluding data charges)

Scenario #1

customer wants to use networking's VPNs to connect a single VPC back to campus. they use their own TGW.

cost breakdown:

VPN attachments from networking - 2 (($0.05(tgw attachment cost)+$0.05(site-to-site vpn cost)) x 2 attachments x 730 hours/month =~ $146/month)
VPC attachment - 1 ($0.05 x 1 attachment x 730 hours/month =~ $36.5/month)

Cost =~ $182.5/month

Scenario #2

customer want to use networking's VPNs to connect a single VPC back to campus. they use centrally offered TGW.

VPC attachment - 1 ($0.05 x 1 attachment x 730 hours/month =~ $36.5/month)

Cost =~ $36.5/month

Allocation

Network Allocation: 10.120.46.0/24

Click here to expand...

vpc-its-tgw-test1

Subnet-1

Name: vpc-its-tgw-test-private-subnet1
CIDR: 10.120.46.0/28
AZ: us-east-1a

Subnet-2

Name: vpc-its-tgw-test-public-subnet1
CIDR: 10.120.46.48/28
AZ: us-east-1e

vpc-its-tgw-test2

Subnet-1

Name: vpc-its-tgw-test-private-subnet2
CIDR: 10.120.46.16/28
AZ: us-east-1e

Subnet-2

Name: vpc-its-tgw-test-public-subnet2
CIDR: 10.120.46.32/28
AZ: us-east-1a