An international company wants to implement a multi-site hybrid infrastructure. The company wants to deploy its cloud computing resources on AWS in the us-east-1 Region and in the eu- west-2 Region, and in on-premises data centers in the United States (US) and in the United Kingdom (UK). The data centers are connected to each other by a private WAN connection. IP routing information is exchanged dynamically through BGP. The company wants to have two AWS Direct Connect connections, one each in the US and the UK. The company expects to have 15 VPCs in each Region with CIDR blocks that do not overlap with each other or with CIDR blocks of the on-premises environment. The VPC CIDR blocks are planned so that the prefix aggregation can be performed both on a Regional level and across the entire AWS environment. The company will deploy a transit gateway in each Region to connect the VPCs. A network engineer plans to use a Direct Connect gateway in each Region. A transit VIF will attach the Direct Connect gateway in each Region to the transit gateway in that Region. The transit gateways will be peered with each other. The network engineer wants to ensure that traffic follows the shortest geographical path from source to destination. Traffic between the on-premises data centers and AWS must travel across a local Direct Connect connection. Traffic between the US data center and eu-west-2 and traffic between the UK data center and us-east-1 must use the private WAN connection to reach the Direct Connect connection to the appropriate Region when the Direct Connect connection is available. The network must be resilient to failures in either the private WAN connection or with the Direct Connect connections. The network also must reroute traffic automatically in the event of any failure. How should the network engineer configure the transit VIF associations on the Direct Connect gateways to meet these requirements?

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B. Advertise VPC-specific CIDR prefixes from only the local Region. Additionally, advertise the Advertising VPC-specific CIDR prefixes from only the local Region (e.g., us-east-1 VPCs via US DX) ensures optimal local routing and allows on-premises to prefer the closest path for local AWS resources. Additionally, advertising the aggregated prefix for *all* AWS regions from *both* Direct Connect locations provides global reachability and redundancy, ensuring all AWS VPCs can be reached from any on-premises location even if one Direct Connect link fails.

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A. Advertise only the aggregate route for the company's entire AWS environment. Advertising only a single aggregate route for the *entire* AWS environment from *both* Direct Connect locations would mean on-premises traffic might not prefer the geographically closest AWS region, leading to suboptimal routing and potentially higher latency.

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C. Advertise all the specific VPC CIDR blocks from both Regions. Advertising all specific VPC CIDR blocks from *both* Regions (i.e., all 30 VPCs via both DXs) creates a very large number of routes and does not leverage the desired prefix aggregation at a regional or global level, increasing administrative overhead and router load.

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D. Advertise both Regional aggregate prefixes. Configure custom BGP communities on the routes Advertising both Regional aggregate prefixes from both DXs provides aggregation, but it might not allow for fine-grained local preference if not combined with more specific local routes, and custom BGP communities are an attribute *for* routing, not a routing strategy that defines what to advertise.

An international company wants to implement a multi-site hybrid infrastructure. The company wants to deploy its cloud computing resources on AWS in the us-east-1 Region and in the eu- west-2 Region…

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