Exam Professional Cloud Network Engineer topic 1 question 124 discussion

C is a better choice.

Option B is likely the more cost-effective solution for minimizing data transfer costs, especially if you want to avoid inter-region traffic over the Google Cloud network and keep the traffic within your on-premises connection.

For B Your Dedicated Interconnect is in us-west2. You can only deploy VLAN attachment in the same region. Why can you deploy a VLAN attachment in us-east4 and us-central 1？Unless you also order Dedicated Interconnect in both us-east4 and us-central1. But the quesion doesn't consider the cost of deploying Interconnect and VLAN attachment. So B can reduce the costs of data transfer across region to minimal and keep the same cost between GCP and on-premises. Finally I choose B.

Option C is a valid solution that involves ordering a new Dedicated Interconnect for a colocation facility closest to us-east4 and using VPC global routing to access workloads in us-central1. This would reduce data transfer costs between us-east4 and the on-premises location, but it would still require data transfer between us-central1 and us-east4 over the Google Cloud network, which may result in additional data transfer costs. Option B, on the other hand, involves keeping the existing Dedicated Interconnect and deploying VLAN attachments to Cloud Routers in both us-east4 and us-central1. This would minimize data transfer costs by keeping traffic between the two regions on the on-premises network and not sending it over the Google Cloud network. It also leverages the existing connection to reduce costs. Therefore, option B is a better solution to minimize data transfer costs when deploying VLAN attachments in this scenario.

B is the better option. VM in same continent, regional routing Cloud Interconnect egress charges for North America No region-to-region egress charges You order an Interconnect connection running from your on-premises location to San Jose (SJC) and create two VLAN attachments over that connection. One VLAN attachment goes to region us-east1, and the other VLAN attachment goes to region us-west1. If you send traffic from a VM in us-east1 or from a VM in us-west1 to your on-premises location over your Interconnect connection in SJC, you are charged the following rates: Cloud Interconnect egress charges for North America (because that is where the Interconnect connection is located). You are not charged region-to-region egress charges because the VMs are using a VLAN attachment in the same region. https://cloud.google.com/network-connectivity/docs/interconnect/pricing#regional-routing

I would go for B https://cloud.google.com/network-connectivity/docs/interconnect/pricing#regional-routing "You are not charged region-to-region egress charges because the VMs are using a VLAN attachment in the same region."

• A. Keep the existing Dedicated interconnect. Deploy a VLAN attachment to a Cloud Router in us-west2, and use VPC global routing to access workloads in us-east4 and us-central1. When you create a VLAN attachment, you associate it with a Cloud Router. This Cloud Router creates a BGP session for the VLAN attachment and its corresponding on-premises peer router. The Cloud Router receives the routes that your on-premises router advertises. These routes are added as custom dynamic routes in your VPC network. The Cloud Router also advertises routes for Google Cloud resources to the on-premises peer router. To utilize multiple VLAN attachments simultaneously for egress traffic in a VPC network, create them in the same ***** region. Then configure your on-premises router to advertise routes with the same MED. The custom dynamic routes, learned through BGP sessions on one or more Cloud Routers that manage the VLAN attachments, are applied to your VPC network with a route priority corresponding to the MED.

No inter-region data transfer cost for B

C. Order a new Dedicated Interconnect for a colocation facility closest to us-east4, and use VPC global routing to access workloads in us-central1.

I think it's B. We can use the same dedicated interconnect, and to reduce data transfer Region-to-region egress charges, we can create vlan attch to each region.

75% workload in us-east4 25% workload in us-central1 Interconnect in us-west2. Minimize data transfer costs = It’s high cost with A and B scenario, because we will continue pay to transfer region data. Letter D is possible, but 25% workload inside this regional (us-central1) we continue pay transfer traffic to us-east4 C is make sense for me, is better scenario to minimize costs with transfer data.

Could also be A instead of C