Azure Virtual Networks vs AWS VPC: Practical Comparison

Azure Virtual Network and Amazon Virtual Private Cloud provide isolated networks for cloud resources. Their basic purpose is similar, but subnet placement, security controls, routing and internet connectivity work differently.

This practical azure vnet vs aws vpc comparison is useful for administrators who manage both platforms or are moving from one cloud to another. For structured Azure networking practice, see the Microsoft Azure AZ-104 course.

What is the main difference between an Azure VNet and an AWS VPC?

An Azure VNet and an AWS VPC are both regional, software-defined networks. The most important architectural difference is that an Azure subnet can contain resources from multiple availability zones, while every AWS subnet belongs to exactly one Availability Zone.

Both services let you define private IP ranges, divide networks into subnets, apply security rules and connect to on-premises networks. However, equivalent components often have different names or attachment points.

How do the network boundaries compare?

A VNet or VPC belongs to one cloud region and cannot stretch directly across regions. Cross-region communication requires services such as global VNet peering, inter-region VPC peering, Azure Virtual WAN or AWS Transit Gateway peering.

Consider an application with web, application and database tiers.

Azure diagram in words:

Azure region
└── VNet 10.10.0.0/16
    ├── web-subnet 10.10.1.0/24
    ├── app-subnet 10.10.2.0/24
    └── db-subnet  10.10.3.0/24

Resources in each subnet may be placed in supported availability zones.

AWS diagram in words:

AWS region
└── VPC 10.20.0.0/16
    ├── public-a  10.20.1.0/24 in Availability Zone A
    ├── private-a 10.20.2.0/24 in Availability Zone A
    ├── public-b  10.20.3.0/24 in Availability Zone B
    └── private-b 10.20.4.0/24 in Availability Zone B

In AWS, a resilient two-zone design normally needs separate subnets in each zone. In Azure, the subnet itself is not assigned to a zone, although individual services or resources may be zonal.

Neither platform allows overlapping address spaces to be connected through normal peering. Address planning should therefore happen before VNets, VPCs, VPNs or private endpoints are deployed.

How do routing and internet access differ?

Azure automatically creates system routes for a subnet, while AWS automatically adds a local route to each VPC route table. Public internet access requires additional resource configuration in both clouds, but AWS uses an explicitly attached Internet Gateway.

In Azure, custom routes are stored in a route table and associated with a subnet. A user-defined route can send traffic to a virtual appliance, virtual network gateway, internet next hop or another supported next-hop type.

In AWS, a public subnet typically has a default route to an Internet Gateway. A private subnet usually sends outbound IPv4 traffic to a NAT Gateway located in a public subnet.

Do not treat a route as a firewall permission. A valid route only selects a path; NSGs, security groups, network ACLs, host firewalls and return routes can still block the session.

Managed NAT services also have architectural differences. An Azure NAT Gateway can be associated with one or more subnets in the same VNet. An AWS NAT Gateway is created in a specific subnet and Availability Zone; production designs commonly deploy one per active zone to reduce cross-zone dependency.

How do Azure and AWS network security controls compare?

Azure NSGs and AWS security groups are stateful. Return traffic for an allowed connection is automatically recognised, but their rule models and attachment options are different.

An Azure NSG can be associated with a subnet, a network interface or both. It supports numbered priorities, service tags, application security groups, and explicit allow or deny rules.

An AWS security group is attached to an elastic network interface and supports allow rules only. AWS Network ACLs operate at the subnet boundary, are stateless, and support both allow and deny entries in rule-number order.

A common migration mistake is trying to reproduce an Azure NSG deny rule inside an AWS security group. Because security groups do not support explicit denies, the design may require removing an allow rule, using a network ACL, or filtering through a firewall.

Use narrow source ranges instead of allowing administrative ports from everywhere. For example, SSH should normally be limited to a trusted management address, VPN range or bastion service.

How do peering, private services and hybrid links compare?

VNet peering and VPC peering create private IP connectivity between networks, but neither service provides general transitive routing. If network A peers with B and B peers with C, A does not automatically reach C through B.

For many-network designs, hub services are easier to operate than a large peering mesh. Azure commonly uses a hub VNet, Azure Virtual WAN or Azure Route Server with a network appliance. AWS commonly uses Transit Gateway.

For private platform-service access, Azure Private Endpoint places a private IP from a subnet onto a supported service connection. AWS interface endpoints create endpoint network interfaces using AWS PrivateLink, while gateway endpoints provide route-table access to supported services such as Amazon S3 and DynamoDB.

Private DNS is critical in both designs. A private endpoint may be reachable by IP while the application still resolves the public service name incorrectly. Check Azure Private DNS zone links or Amazon Route 53 private hosted zones and endpoint DNS settings when this happens.

For broader AWS design practice, the AWS Solutions Architect course covers VPC connectivity alongside compute, storage and identity services.

Practical lab: create an Azure VNet with the Azure CLI

This lab creates a resource group, VNet, subnet and NSG. It then permits SSH only from the documentation address 203.0.113.10/32; replace that value with your actual trusted public address before using the configuration.

az login

az group create \
  --name rg-network-lab \
  --location centralindia

az network vnet create \
  --resource-group rg-network-lab \
  --name vnet-lab \
  --address-prefixes 10.10.0.0/16 \
  --subnet-name snet-web \
  --subnet-prefixes 10.10.1.0/24

az network nsg create \
  --resource-group rg-network-lab \
  --name nsg-web \
  --location centralindia

az network nsg rule create \
  --resource-group rg-network-lab \
  --nsg-name nsg-web \
  --name allow-ssh-admin \
  --priority 100 \
  --direction Inbound \
  --access Allow \
  --protocol Tcp \
  --source-address-prefixes 203.0.113.10/32 \
  --source-port-ranges '*' \
  --destination-address-prefixes '*' \
  --destination-port-ranges 22

az network vnet subnet update \
  --resource-group rg-network-lab \
  --vnet-name vnet-lab \
  --name snet-web \
  --network-security-group nsg-web

Confirm the subnet prefix and NSG association:

az network vnet subnet show \
  --resource-group rg-network-lab \
  --vnet-name vnet-lab \
  --name snet-web \
  --query '{prefix:addressPrefix,nsg:networkSecurityGroup.id}' \
  --output table

This configuration does not create a virtual machine, public IP or explicit outbound NAT path. In a real environment, plan outbound connectivity with Azure NAT Gateway, Azure Firewall or another controlled method instead of depending on implicit platform behaviour.

Practical lab: create an AWS VPC with the AWS CLI

This example creates a VPC, one public subnet, an Internet Gateway, a route table and a security group. The selected Availability Zone must exist in the configured AWS Region.

aws configure

VPC_ID=$(aws ec2 create-vpc \
  --cidr-block 10.20.0.0/16 \
  --query 'Vpc.VpcId' \
  --output text)

aws ec2 modify-vpc-attribute \
  --vpc-id "$VPC_ID" \
  --enable-dns-hostnames '{"Value":true}'

SUBNET_ID=$(aws ec2 create-subnet \
  --vpc-id "$VPC_ID" \
  --cidr-block 10.20.1.0/24 \
  --availability-zone ap-south-1a \
  --query 'Subnet.SubnetId' \
  --output text)

IGW_ID=$(aws ec2 create-internet-gateway \
  --query 'InternetGateway.InternetGatewayId' \
  --output text)

aws ec2 attach-internet-gateway \
  --internet-gateway-id "$IGW_ID" \
  --vpc-id "$VPC_ID"

RT_ID=$(aws ec2 create-route-table \
  --vpc-id "$VPC_ID" \
  --query 'RouteTable.RouteTableId' \
  --output text)

aws ec2 create-route \
  --route-table-id "$RT_ID" \
  --destination-cidr-block 0.0.0.0/0 \
  --gateway-id "$IGW_ID"

aws ec2 associate-route-table \
  --route-table-id "$RT_ID" \
  --subnet-id "$SUBNET_ID"

SG_ID=$(aws ec2 create-security-group \
  --group-name sg-web \
  --description 'Web lab security group' \
  --vpc-id "$VPC_ID" \
  --query 'GroupId' \
  --output text)

aws ec2 authorize-security-group-ingress \
  --group-id "$SG_ID" \
  --protocol tcp \
  --port 22 \
  --cidr 203.0.113.10/32

A route to the Internet Gateway does not by itself make an EC2 instance publicly reachable. The instance also needs a public IPv4 address or Elastic IP, an attached security group permitting the traffic, a suitable network ACL and a listening service.

Infrastructure teams can automate both labs with reusable code. The guide to Terraform modules and remote state explains how to separate network components and manage shared state safely.

How should you troubleshoot connectivity in each cloud?

Start with the expected traffic path, then verify DNS, addressing, routes, cloud security controls and the guest operating system. Checking only an NSG or security group often misses an incorrect route, failed name resolution or a service that is not listening.

1. Confirm IP addressing and DNS

On a Linux workload, check its address, routes and name resolution:

ip address
ip route
getent hosts api.example.internal
dig api.example.internal

Confirm that source and destination ranges do not overlap unexpectedly. For private endpoints, verify that the hostname resolves to the intended private IP.

2. Test the destination port

nc -vz 10.10.2.20 443
curl -vk --connect-timeout 5 https://10.10.2.20/
ss -lntp

A timeout usually indicates filtering, routing or a silent application path failure. An immediate connection refusal normally means the host is reachable but no process is listening on that port, or the host actively rejected it.

3. Inspect effective Azure controls

For a VM network interface, review effective routes and security rules:

az network nic show-effective-route-table \
  --resource-group rg-network-lab \
  --name nic-web-01 \
  --output table

az network nic list-effective-nsg \
  --resource-group rg-network-lab \
  --name nic-web-01

Also check whether an NSG exists at both subnet and NIC level. Traffic must be allowed by the combined effective rules.

4. Inspect AWS routes and security groups

aws ec2 describe-route-tables \
  --filters "Name=association.subnet-id,Values=$SUBNET_ID"

aws ec2 describe-security-groups \
  --group-ids "$SG_ID"

aws ec2 describe-network-acls \
  --filters "Name=association.subnet-id,Values=$SUBNET_ID"

For a stateless network ACL, inspect both directions. An inbound application rule can still fail if return traffic on the relevant ephemeral ports is blocked.

5. Use platform diagnostics

Azure Network Watcher provides IP flow verification, connection troubleshooting, next-hop analysis and packet capture features. AWS provides Reachability Analyzer, VPC Flow Logs and Traffic Mirroring for supported investigation scenarios.

Flow logs show accepted or rejected network flows, not application content. Use them to identify source addresses, destination ports and filtering results, then inspect application logs separately.

Which platform is easier for network engineers?

Neither model is universally easier; familiarity usually determines which feels more natural. AWS exposes Availability Zone boundaries directly through subnets, while Azure often feels simpler for regional subnet design but uses several platform-specific routing and private connectivity concepts.

Choose based on the environment you need to operate. More importantly, practise mapping requirements rather than memorising names: subnet isolation, stateful filtering, explicit outbound access, resilient routing, DNS and observability apply to both platforms.

Summary

• Azure VNets and AWS VPCs are regional isolated networks.
• Azure subnets are not tied to one availability zone; AWS subnets are.
• Azure NSGs support allow and deny rules, while AWS security groups support allows only.
• AWS Network ACLs are stateless subnet filters with ordered allow and deny rules.
• Routes and security permissions are separate decisions in both clouds.
• Peering is not generally transitive, so large environments need a planned hub architecture.
• Private service connectivity depends on correct routing, security and private DNS.
• Troubleshooting should follow the full packet path from name resolution to the listening application.

Reviewed by Network Rhinos cloud networking trainers.

To practise Azure VNets, NSGs, routes, private endpoints and hybrid connectivity in guided labs, enquire about upcoming batches for the Microsoft Azure AZ-104 course.