My journey to AWS Solution Architect Exam — Part 12 –Site-to-Site VPN, VPN CloudHub, Direct Connect
AWS Site-to-Site VPN stands as a crucial service for organizations seeking to extend their on-premises network infrastructure into the AWS cloud. Its architecture involves several key components, each playing a pivotal role in ensuring a secure and reliable connection between the client’s systems and the AWS cloud environment.
Virtual Private Gateway (VGW)
VGW serves as the central point in the AWS cloud for the VPN connection. Created and associated with a Virtual Private Cloud (VPC), the VGW acts as the virtual gateway, bridging the client’s on-premises network and the target VPC. The customization of the Autonomous System Number (ASN) provides flexibility in uniquely identifying the client’s network within the autonomous system on the Internet.
Customer Gateway (CGW)
On the other side of the connection, the Customer Gateway (CGW) serves as the entry point into the client’s network. This can be implemented as either a software application or a physical device.
The connection between the CGW and VGW creates a secure tunnel through which data can flow reliably between the on-premises environment and the AWS VPC.
The following passage provides guidance on the necessary configurations and considerations for the customer-side of the Site-to-Site VPN connection, including the IP address settings, handling NAT traversal, enabling route propagation, and configuring security groups for specific protocols like ICMP if needed.
- What IP address to use? Specifies the IP address that should be configured on the customer’s gateway device. The customer gateway device should have a public IP address that is reachable over the internet.
- If it’s behind a NAT device that’s enabled for NAT traversal (NAT-T), use the public IP address of the NAT device.
- Important step: enable Route Propagation for the Virtual Private Gateway in the route table that is associated with your subnets: this is essential for proper routing of traffic between the on-premises network and the AWS VPC.
- If you need to ping your EC2 instances from on-premises, make sure you add the ICMP protocol on the inbound of your security groups: it’s important to configure the security groups associated with the EC2 instances to allow inbound ICMP traffic.
AWS VPN CloudHub
AWS VPN CloudHub is a solution that provides secure and cost-effective communication between multiple sites through a hub-and-spoke model. It leverages VPN connections over the public Internet and requires the configuration of multiple VPN connections on the same Virtual Private Gateway, along with dynamic routing and route table configurations for optimal network connectivity.
AWS VPN CloudHub is designed to establish secure communication channels between multiple sites within a network infrastructure.
It operates on a hub-and-spoke model, providing a cost-effective solution for network connectivity between different locations. In this model, the hub serves as a central point that connects to multiple spoke sites and serves as a low-cost option for both primary and secondary network connectivity between various locations. This connectivity is established through VPN connections.
To set up AWS VPN CloudHub, you need to connect multiple VPN connections on the same Virtual Private Gateway (VGW). The VGW acts as the central hub, connecting to the VPNs associated with different locations while dynamic routing is employed in the setup, allowing for automatic and efficient route updates. Additionally, route tables are configured to manage the flow of traffic between the hub and spoke sites, ensuring that data is directed appropriately.
AWS Direct Connect
AWS Direct Connect establishes a dedicated, private connection between on-premises data centers and AWS VPCs, providing benefits such as increased bandwidth throughput, a consistent network experience for real-time applications, and support for hybrid environments with both IPv4 and IPv6 compatibility.
A dedicated physical connection (over a standard Ethernet fiber-optic cable) must be set up between the customer’s data center and AWS Direct Connect locations. This ensures a reliable and secure link between the on-premises network and the AWS cloud. To facilitate the connection, a Virtual Private Gateway (VGW) needs to be set up on the customer’s VPC. The VGW acts as the endpoint for the AWS side of the Direct Connect link.
Direct Connect Gateway
To connect to multiple Virtual Private Clouds (VPCs) in different AWS regions within the same AWS account using AWS Direct Connect, you would indeed utilize a feature called Direct Connect Gateway.
It’s a global construct that allows you to connect your AWS Direct Connect connection to multiple VPCs across different AWS regions within the same AWS account.
It simplifies the network architecture and management by providing a single connection from your on-premises network to the Direct Connect Gateway, and then the Direct Connect Gateway can be associated with multiple VPCs across various regions.
Instead of setting up individual Direct Connect connections for each VPC in different regions, you can associate the Direct Connect Gateway with the relevant VPCs. This makes it easier to manage the connectivity and reduces the complexity of the network configuration: you can manage your connections from a single point, providing a more streamlined and efficient approach to network management.
This architecture is particularly useful for organizations with a presence in multiple AWS regions, allowing them to establish a unified and manageable Direct Connect connection to serve their global infrastructure.
Encryption considerations
AWS Direct Connect provides a private connection, but data in transit is not encrypted by default.
For organizations requiring an additional layer of security, combining AWS Direct Connect with a VPN is a recommended approach. This enhances security through IPsec encryption, but it does add a bit more complexity to the setup compared to using Direct Connect alone.
When AWS Direct Connect is combined with a VPN, IPsec is employed to encrypt the data flowing over the connection.
Considerations
The choice between VPN and Direct Connect depends on factors such as data transfer requirements, security considerations, and the level of dedicated, private connectivity needed. Many organizations use a combination of both, tailoring their network architecture to meet specific needs across different scenarios.
- Bandwidth: Direct Connect offers more consistent and potentially higher bandwidth compared to VPNs.
- Security: While Direct Connect is inherently more private, VPNs can provide additional encryption for security.
- Cost vs Performance: The choice between VPN and Direct Connect often involves a trade-off between cost and performance based on the specific needs and requirements of the organization.
