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In this configuration, the Cornell campus network will route network traffic to the VPC's private address space over the Direct Connect. The DCGW+TGW infrastructure connected to the AWS VPC will route any Cornell Private Network traffic not destined for Cornell VPCs in AWS back to the Cornell campus network via Direct Connect. This effectively leverages the Direct Connect as an extension of the Cornell Private Network.
Traffic from the VPC destined for other Cornell AWS VPCs will transit the DCGW+TGW infrastructure or dedicated peering connections, without exiting AWS.
Design Decisions
When using the Private Network Extension model:
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In this configuration, the Cornell campus network will route network traffic to the VPC's private address space over the Direct Connect. In conjunction, the Virtual Private Gateway in the The DCGW+TGW infrastructure connected to the AWS VPC will route both Cornell Private Network traffic and Cornell Public Network traffic back to the Cornell campus network via Direct Connect. As in the Private Network Extension configuration discussed earlier, VPC traffic destined for the VPC itself, or any configured VPC peering connections will remain within AWS and not sent back to campus over the Direct Connect.
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