Compare Amazon VPC vs. Azure VNet for private networking

Amazon VPC overview

Amazon VPC enables users to launch AWS resources in a defined virtual network. This means that workloads running within a VPC are isolated at the network level. They can only connect to resources outside of the VPC if the customer configures them accordingly.

With VPC, Amazon 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 using public networks.
• Establish VPNs and institute fine-grained security practices.

Notable features of Amazon VPC include the following:

Subnetting

Subnetting is a core component of the VPC experience. Subnets allow you to divide a VPC, which is a logically isolated environment, into smaller units and control the flow of data between each unit.

Different teams within an organization often have diverse resources that they want to keep private, but they also need to be able to share data with other users or teams. By creating VPCs and subnets, these teams can accomplish this. For example, Fortinet, Trend Micro and IBM tools can coexist harmoniously within separate subnets to strengthen cybersecurity.

Each Amazon VPC subnet has its own IPv4 address. The service also supports IPv6, which offers superior routing, simplicity, configurability and standard end-to-end encryption.

Peering

Customers can enable peering connections to route traffic directly between VPCs using private IPv4 and IPv6 addresses. This can boost performance in cases where administrators need separate logical environments for workloads but still want to share data between them rapidly.

Peering is also beneficial for disaster recovery, since it enables fast movement of data between VPCs located in different cloud regions or between separate accounts. If one region fails, workloads remain available in the other region.

Another benefit of these connections is their reliance on existing VPC infrastructure through AWS, rather than separate hardware. This prevents single points of failure and network bottlenecks.

Integration

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

• Execute functional, serverless code.
• Store data remotely, restricting availability to certain VPC instances or tools.
• Connect networking resources with instances to access scalable cloud computing capacity.

Other AWS networking services can also implement these capabilities. AWS Transit Gateway forges a unified connection between VPCs, AWS accounts and on-premises networks. AWS PrivateLink creates a secure pathway between active AWS services and VPCs.

Customization

Organizations can use the AWS Management Console or the AWS CLI to launch and customize VPCs.

There is room for ample customization within Amazon VPCs. Users can configure public and private subnets and route tables, gateways and security considerations. For example, VPC enables network access control list and security group setups, which act as firewalls and filter for network traffic.

Observability

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 insights into suspicious events. Amazon CloudWatch also provides stakeholders with relevant monitoring and observability metrics.

Additionally, VPC Traffic Mirroring permits outbound exchange and inspects packets to squash threats and troubleshoot transfer issues. If two resources have trouble communicating, the VPC Reachability Analyzer can highlight connection bottlenecks and barriers to enable quick remediation.

Azure VNet overview

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

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.
• Integration with Azure services.

The following are some of the key features of Azure VNet:

Peering

Though VNets are isolated, it does not mean they can't communicate. A VNet peering connection enables communication between virtual networks using IPv4 or IPv6 addresses.

Data can flow back and forth as admins deem necessary, or according to the organization's configurations. Microsoft also acknowledges the role IPv6 plays in supporting IoT device communication. Service instances can dually connect with clients using both protocols.

Customization

Users can create and configure Azure VNets through the Azure Portal, Azure CLI or PowerShell. Some capabilities that users can configure in Azure VNets are routing and gateways. Dubbed User-Defined Routing (UDR), Azure runs a default routing 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, comparable to those supported by Amazon VPC. These virtual networks can connect with Azure App Service Environments, Azure Kubernetes Service or Azure Virtual Machine Scale Sets, for example.

VPN options

Like VPC, Azure VNet enables users to 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. Users can also provision a VM as a firewall -- or to support a goal like WAN optimization.

The Amazon VPC vs. Azure VNet breakdown

Let's examine both tools side by side to see how they compare:

Amazon VPC and Azure VNet share more commonalities than differences. But there are some nuanced distinctions between them, such as:

• Route management. Amazon VPC uses route tables to manage traffic flows between subnets and VPCs. Azure VNet uses system routes, which means traffic can flow automatically.
• Internet connectivity. Amazon VPC uses an Internet Gateway to manage traffic flowing between VPC environments and the Internet. Azure VNet uses public IPs.

These might seem like minute differences that don't matter much. However, these differences have implications for the UX. Azure VNet is often considered a simpler, more intuitive service to manage, partly because its use of system routes and routing tables reduces the amount of complexity that admins need to manage when defining routing rules.

Beyond this, however, the services are very comparable in areas like pricing and their ability to support load balancing. Practically speaking, they are each equally scalable; Azure VNet limits users to 1,000 networks per subscription -- more than most organizations are likely to need -- whereas there is no hard limit in Amazon VPC.

Amazon VPC vs. Azure VNet for your organization

In most cases, the most important factor to consider when choosing between Amazon VPC and Azure VNet is not the nuanced differences between these services. Rather, it's which cloud -- AWS or Azure -- is the overall better fit for the organization and its workloads. The distinctions between VPC and VNet are too minor to justify selecting an entire cloud platform based on them.

That said, if UX is a priority, it's likely that teams will find Azure VNet to be a simpler service to configure. Routing can also be slightly more efficient with Azure's virtual networking service.

This article was originally written by Adam Bertram and expanded by Chris Tozzi.

Chris Tozzi is a freelance writer, research adviser, and professor of IT and society. He has previously worked as a journalist and Linux systems administrator.