Configuring existing on-premises networks to connect with the AWS Cloud

What AWS service would you use to establish a dedicated network connection from an on-premises network to AWS?

AWS Direct Connect. The service allows for the establishment of a private, dedicated network connection from an on-premises network to the AWS network, which can reduce network costs, increase bandwidth throughput, and provide a more consistent network experience than internet-based connections.

Can you explain how the AWS Site-to-Site VPN service works and when it’s suitable to use it?

AWS Site-to-Site VPN creates a secure connection between an on-premises network and your Amazon Virtual Private Cloud (VPC). It’s suitable for scenarios where you need a quick, easy, and secure connection without the longer lead times associated with AWS Direct Connect, or for backup connectivity solutions.

How would you configure redundant VPN connections to ensure high availability?

To configure redundant VPN connections for high availability, you would set up multiple VPN connections from your on-premises network to the AWS VPC, ideally using different customer gateways and terminating on different virtual private gateways on the AWS side. Implementing dynamic routing protocols such as BGP is also recommended to manage the failover automatically.

What are some of the things you should consider when sizing an AWS Direct Connect link?

When sizing an AWS Direct Connect link, you should consider the bandwidth requirements of your applications, the amount of data that will be transferred over the connection, potential growth or spikes in traffic, and the performance requirements such as latency and throughput. Redundancy and cost are also important factors to weigh.

Describe how you would migrate an existing on-premises application to AWS, ensuring minimal downtime and high network performance.

To ensure minimal downtime and high network performance, you would begin by assessing the application’s network dependencies and bandwidth requirements. Implement AWS Direct Connect or a highly available VPN setup for reliable network connectivity. Use services such as AWS Database Migration Service (DMS) for database migration and Elastic Load Balancing (ELB) to distribute traffic. Plan and test the migration carefully to identify and mitigate risks, ensuring a rollback strategy is in place.

How does AWS Transit Gateway simplify network connectivity?

AWS Transit Gateway simplifies network connectivity by acting as a cloud router that interconnects VPCs and on-premises networks through a central hub. This reduces the complexity of managing multiple peering connections and routing policies, enabling a scalable way to grow the network and simplify the network management.

What is the difference between AWS Direct Connect and AWS VPN in terms of latency and security?

AWS Direct Connect generally provides lower latency compared to AWS VPN because it’s a dedicated private connection that doesn’t traverse the public internet. In terms of security, both services provide secure connections; however, AWS Direct Connect requires additional encryption mechanisms at a higher layer if encryption is necessary, while AWS VPN connections are encrypted by default at the network layer using IPsec protocols.

When connecting your on-premises network to AWS, how would you ensure your network traffic remains private?

To ensure network traffic remains private when connecting on-premises networks to AWS, use a service like AWS Direct Connect with private virtual interfaces to route traffic directly to your Amazon VPC without accessing the public internet. For additional encryption over Direct Connect, implement VPN tunnels or transport layer security using encryption appliances or built-in functions of your applications.

How can you manage overlapping IP addresses when connecting your on-premises network to a VPC?

To manage overlapping IP addresses, use VPC Peering, AWS Direct Connect, or VPN connections along with Non-Overlapping CIDR blocks, or implement Network Address Translation (NAT) to map one range of IP addresses to another. This prevents any routing conflicts and allows smooth communication between the on-premises network and AWS VPC.

What steps would you take to monitor and troubleshoot the network performance of your AWS and on-premises hybrid environment?

To monitor and troubleshoot the network performance of a hybrid environment, implement AWS CloudWatch for metrics and logs, AWS CloudTrail for API and networking actions tracking, and use VPC Flow Logs to collect network traffic flow data. Additionally, consider using third-party network performance monitoring tools that are compatible with AWS services. For troubleshooting, systematically work through network layers (physical, data link, network, and transport) to identify and resolve issues.

Can you explain what AWS Global Accelerator is and when you would use it?

AWS Global Accelerator is a networking service that improves users’ access to your applications by directing traffic through AWS’s global network infrastructure, thereby enhancing performance and reliability. You would use AWS Global Accelerator when you want to improve the availability and performance of your applications for a global audience, and when you have users that need consistent, low-latency access regardless of their geographical location.

Describe how you would secure data in transit from on-premises to AWS and vice versa.

To secure data in transit from on-premises to AWS, you can use AWS Direct Connect with private virtual interfaces in combination with higher-layer encryption protocols like TLS or IPsec VPN natively supported by AWS. Implement strict access control with AWS Identity and Access Management (IAM), enforce encryption with services such as AWS Certificate Manager, and utilize robust encryption mechanisms within your application stack.