Compare Amazon VPC vs. Azure VNet for private networking

Amazon VPC overview

Amazon VPC has a simple purpose: Launch AWS resources in a defined virtual network. AWS provides the infrastructure and the user configures functionality as desired. Amazon asserts that users have complete control over their networking. With the VPC, users can perform the following tasks:

• choose IP addresses and their ranges;
• create subnets;
• configure route tables and gateways;
• isolate back-end systems on a private subnet;
• make web-connected systems available to users via public networks; and
• establish VPNs and institute fine-grained security practices.

That last bullet comes with a qualifier: Users can create VPNs for on-premises resources, but they're not required for cloud-only networking. Some notable features of Amazon VPC include:

Subnetting

Subnetting is a core component of the VPC experience. Envision a public subnet as a country with a secured border crossing, and a private subnet as a nation surrounded by impregnable walls.

Different teams have diverse resources. While organizations don't want to expose their servers to users, those users might need access to websites, applications and extended corporate networks. Teams can bolster these VPCs with added safety measures. For example, Fortinet, Trend Micro and IBM tools coexist harmoniously with VPC routing to strengthen cybersecurity.

Each Amazon VPC subnet has its own IPv4 address. The service also supports IPv6. These internet protocols provide web access for networking resources. IPv6 support offers superior routing, simplicity, configurability and standard end-to-end encryption.

Integration

Amazon VPC fits squarely within the AWS ecosystem. The service integrates with AWS Lambda, Amazon S3 and Amazon EC2. You can therefore:

• execute functional, serverless code;
• store data remotely, making it only available to certain VPC instances or tools; and
• connect networking resources with instances, to access scalable cloud-computing capacity.

The same goes for AWS Transit Gateway, which forges a unified connection between VPCs, AWS accounts and on-premises networks. Similarly, AWS Private Link creates a secure pathway between active AWS services and VPCs.

Customization

Organizations can also use the AWS Management Console or the Command Line Interface to launch new VPCs. Amazon VPC is focused on efficiency and security while it also provides ample customization. Configurations are integral to creating segregated and unified workloads. VPC lets you set up a network access control list, which acts as a firewall and filter for network traffic.

Observability

Lastly, Amazon VPC emphasizes observability -- both actively and retroactively. With VPC Flow Logs, ops teams have visibility into traffic allocation, network activity, data sharing and compliance, as well as highlights into suspicious events. Additionally, VPC Traffic Mirroring permits outbound exchange and inspection of packets to squash threats and troubleshoot transfer issues.

If two of your resources have trouble communicating, the VPC Reachability Analyzer can highlight connection bottlenecks and barriers to enable you to quickly remediate issues.

Azure VNet overview

Azure VNet connects Azure VMs and computing resources with one another, as well as on-premises networks and the internet as a whole. While Azure VNets share foundational infrastructure, they remain isolated from one another by default. Azure Networking uses virtual extensible LANs to securely link virtual networks, while remaining scalable in the process.

However, just because VNets are isolated does not mean they can't communicate. A VNet peering connection lets these virtual networks "chat" using IPv4 or IPv6. Data can flow back and forth as admins deem necessary, according to the organization's configurations. Microsoft also acknowledges the role IPv6 plays to support IoT device communication. Service instances can dually connect with clients using both protocols.

With VNet, admins can enable:

• communication of Azure resources with the internet;
• communication between Azure resources;
• communication with on-premises resources;
• filtering of network traffic;
• routing of network traffic; and
• integration with Azure services.

Like Amazon VPC, Azure VNet employs routing tables to dictate how traffic flows from resources. Dubbed User-Defined Routing (UDR), Azure runs a default configuration that welcomes customization. These user routes often take precedence over default routes. With Azure VPN Gateway, UDR can also control traffic between virtual networks and others.

To connect on-premises networks with VNet gateways, admins can use border gateway protocol (BGP) routing. BGP adds a separate route to all existing route tables that belong to VNet subnets -- the source becomes a virtual network gateway.

Integration

Azure VNets can host a litany of native Azure services, much like Amazon VPC. These virtual networks connect with Azure App Service Environments, Azure Kubernetes Service or Azure Virtual Machine Scale Sets. Since it deals with data, VNet interfaces directly with current Azure Storage accounts and Azure SQL Database. It's easy to privately store and safeguard VNet information.

VPN options

Azure VNet also lets you create two types of VPNs. The first, point-to-site VPN, creates a connection between a virtual network and one computer on another network. Microsoft views this as more of a plug-and-play setup, since little configuration is required to get started.

Secondly, site-to-site VPNs connect a VNet-deployed, Azure VPN Gateway with an on-premises VPN device. These connections rely on explicit authorization. They also use encrypted tunneling.

Finally, network security groups contain two-way security rules, enforced according to IP address, port, firewall, source and destination. You can additionally provision a VM as a firewall -- or for something like WAN optimization.

The Amazon VPC vs. Azure VNet breakdown

Amazon VPC and Azure VNet share more commonalities than differences. Each focuses on security, integration and performance in similar ways. For example, the two are similar in these important areas:

Network address translation (NAT) gateways. These gateways forge restricted, one-way connections between private subnets and the internet. Both Azure and Amazon offer NAT functionality at identical prices of $0.045 per hour.

Load balancing. Azure VNet offers public load balancing for controlling VM traffic distribution within a VNet, and private load balancing to balance internal VNet traffic. Amazon's Elastic Load Balancing offers similar functionality.

In terms of which is better, it largely depends on use case. VNet seems more enterprise focused, whereas Amazon VPC is ideal for more customer-facing resources -- per AWS' use cases.

When you make the choice between Amazon VPC and Azure VNet, consider the following:

• What will your networks control?
• What services are you focusing on?
• Are you already familiar with one technology stack over the other?

Teams often stick with vendors they know, since transitions can be painful. Ultimately, the decision will depend on which service's subtleties are most useful for your organization's needs.