AWS networking services and DNS (for example, Direct Connect, AWS Site-to-Site VPN, Route 53)

Can you describe what AWS Direct Connect is and how it differs from AWS Site-to-Site VPN?

AWS Direct Connect is a cloud service that allows you to establish a dedicated network connection from your premises to AWS. By bypassing the public internet, it provides a more consistent network experience compared to internet-based connections. In contrast, AWS Site-to-Site VPN is a VPN service that enables you to create an encrypted tunnel over the internet between your on-premises network and your AWS VPC. Direct Connect offers higher bandwidth options and reduced network costs but requires a physical connection at a Direct Connect location, while Site-to-Site VPN can be established over an existing internet connection and offers encryption.

How does Amazon Route 53 provide high availability and scalability for DNS management?

Amazon Route 53 is a highly available and scalable cloud DNS web service. It is designed to give developers and businesses an extremely reliable and cost-effective way to route end users to internet applications. Route 53 achieves high availability by using a global network of DNS servers, which ensures that DNS queries are answered with great speed and reliability. It scales automatically to handle large query volumes without any intervention on the user’s part.

What are the benefits of using AWS Transit Gateway in a complex network architecture?

AWS Transit Gateway simplifies network architecture and operations by acting as a hub that controls how traffic is routed among all the connected networks which can include VPCs, AWS Direct Connect connections, and VPNs. This central hub reduces the complexity of managing multiple point-to-point peering connections, and offers simple management, easier scalability, and more efficient networking.

Explain the difference between static and dynamic routing options in AWS Site-to-Site VPN, and when you would use each.

Static routing in AWS Site-to-Site VPN involves manually specifying the IP prefixes (routes) that are reachable through the VPN connection. It is straightforward and ideal for simple, unchanging network topologies. Dynamic routing, using BGP, automatically updates the routes as your network changes, which reduces the need for manual configuration. It is used for complex networks with frequently changing routes.

What are security best practices when setting up AWS Direct Connect?

Some security best practices for AWS Direct Connect include:
– Implementing strict access controls and monitoring on the Direct Connect gateway,
– Using AWS Direct Connect in conjunction with virtual private clouds (VPCs) to ensure encrypted data flows,
– Implementing network segmentation and segregation to minimize the impact of potential breaches,
– Regularly monitoring network traffic for unusual activity,
– and ensuring physical security at the Direct Connect location.

Why would a company opt for multi-region VPC peering, and what does AWS offer to support this functionality?

A company might opt for multi-region VPC peering to ensure low-latency access to resources in multiple AWS regions, improve disaster recovery capabilities, or meet compliance requirements for geographic data storage. AWS has introduced the capability to create VPC peering connections across different AWS regions (inter-region), offering the same latency and bandwidth levels as if the services were in the same VPC within a single region.

Can you explain the importance of Amazon Route 53 health checks and how they work?

Amazon Route 53 health checks monitor the health and performance of your application endpoints, such as web servers and email servers. The service sends automated requests to your application to verify that it’s reachable, available, and functional. If a health check fails, Route 53 can reroute the traffic to healthy endpoints or to a static error page, which increases the availability of your application.

Describe the situations in which you would choose a NAT gateway over a NAT instance in AWS.

You would choose a NAT gateway over a NAT instance in situations where you require high availability, scalability, and bandwidth without the need to manage the underlying infrastructure. NAT gateways are AWS managed services and are automatically scaled to accommodate most workloads, whereas NAT instances are EC2 instances acting as a NAT and require manual management and scaling.

How can AWS Global Accelerator improve the performance of an application?

AWS Global Accelerator improves the performance of an application by directing user traffic through the AWS global network infrastructure. It automatically routes user traffic to the nearest edge location and then to the application endpoints in AWS regions. This minimizes network congestion and latency, improving the application’s overall performance and user experience.

What measures should be taken to secure Amazon Route 53 DNS records and prevent DNS hijacking?

To secure Route 53 DNS records and prevent DNS hijacking, you should:
– Implement DNSSEC to authenticate the origin of DNS data and ensure data integrity,
– Use Route 53 Resolver Query Logging for visibility and to monitor DNS queries,
– Employ identity and access management (IAM) policies to control who can alter DNS records,
– and consider using Route 53 Resolver Firewall to mitigate DNS-level threats.

In what scenarios is AWS Site-to-Site VPN preferred over AWS Direct Connect?

AWS Site-to-Site VPN is preferred over AWS Direct Connect in scenarios where a company requires quick setup, desires encrypted connectivity over the public internet, is seeking a low-cost option, or doesn’t require the high bandwidth and low-latency connections that Direct Connect offers. It is also a good choice for businesses with fluctuating connectivity needs or those without access to a Direct Connect location.

What is the purpose of AWS PrivateLink, and how does it enhance network security?

AWS PrivateLink allows you to securely connect your VPC to supported AWS services, services hosted by other AWS accounts (VPC endpoint services), and supported AWS Marketplace partner services without exposing your traffic to the public internet. This reduces the risk of internet-based attacks and enhances network security by providing private connectivity between your services and VPCs.