A Cloud Networking Primer: Building Your Network in the Azure Cloud


Today’s cloud-centric ecosystem demands efficient computing tools and high-performing applications. Microsoft Azure provides a reliable network architecture that helps manage resources in the cloud. In this article, Gilad David Maayan, CEO, Agile SEO, discusses the scope of Azure networking capabilities, core services, the costs associated and how organizations can explore and benefit from the various networking options in the Azure cloud.

What Is Azure Networking?

Networking is essential for cloud infrastructure—it allows IT teams to connect computing resources and achieve optimal performance for their applications. Microsoft Azure provides a reliable network architecture through its networking services, which help you manage resources in the cloud.

In addition to various connectivity options and virtual networks, Azure provides tools and capabilities such as monitoring and managing network traffic, performing load balancing, and maintaining secure connections.

What Are Azure’s Key Networking Capabilities?

Azure’s offerings come with scalability, high availability, and enterprise-grade security to manage heavy workload requirements besides providing smooth integration across on-premises, multi-cloud, and edge locations.Here are the four key capabilities that you can leverage:

1. Routing Optimization 

Azure lets you optimize routing for improved performance. Cold potato routing keeps network traffic on Microsoft’s global network to ensure reliability and low latency. A multi-region or multi-AZ hosting architecture can help make your cloud deployments more resilient and reduce latency to less than one millisecond. 

Azure offers the following services to help you optimize routing:

  • Azure ExpressRoute—provides reliable performance of up to 100 GB per second.
  • Azure Peering—provides optimized connectivity with a software-defined wide area network (SD-WAN) and software as a service (SaaS).
  • Azure Load Balancer—directs traffic to utilize available resources and achieve optimal performance and low latency.
  • Routing preferences—let you specify traffic routes between the Internet and Azure.

2. Zero Trust Network Security

A zero trust security approach lets you protect your networks, workloads, and applications by assuming that no user or entity is trustworthy.

Azure offers the following services to support zero trust security:

  • Microsegmentation—helps secure virtual networking infrastructure.
  • Azure WAF—a web application firewall to protect your applications.
  • Azure Bastion—helps secure your virtual machines.
  • Azure DDoS Protection—provides intelligence-based threat detection.
  • Azure Private Link—provides private connectivity for a more secure network.

3. Edge and Hybrid Connectivity

Azure can act as an extension of existing networks, delivering applications to end-users anywhere. Azure lets you connect various deployments to enable centralized management and control over your extended network.

Azure offers the following connectivity options:

  • Azure Virtual WAN—a wide area network that connects branch, hybrid, multi-cloud, and on-premises deployments.
  • Azure Edge Zones—provide 5G and edge capabilities. You can use Edge Zones as is or with a carrier, and there is a private option. 

4. Network-as-a-Service

Azure provides networking capabilities as a service, allowing you to focus on developing your applications with intuitive, scalable tools. Azure Networking offers the scale and connectivity you require, and you don’t have to build or maintain the infrastructure. 

Azure offers the following networking services:

  • Azure App Gateway—manages application traffic.
  • Azure Front Door—lets you specify routing and provides monitoring capabilities.
  • Azure Firewall—offers turnkey firewall functionality.
  • VNet NAT—ensures predictable outbound connectivity from a secure IP.

See More: AWS vs Azure: Your Guide to Choosing the Best Cloud Provider 

Azure Networking Core Services

Most organizations have unique networking needs. Azure offers multiple services to choose from, keeping those specific needs in mind. Here are the seven core services provided by Azure:

1. Azure Virtual Network (VNet)

Azure VNet is the central component of a private virtual network in Azure. VNet enables secure communication between various Azure resources, including virtual machines (VMs). It also lets resources communicate with your on-premise network and the public Internet. VNet operates much like a traditional data center-based—the main difference is that it enables you to leverage the Azure cloud infrastructure to achieve high availability, scalability, and security (isolation).

2. Azure Load Balancer

A load balancer lets you distribute incoming network traffic across various backend servers or resources to ensure consistent performance. Azure Load Balancer works at the transport layer (Layer 4) to maintain high availability. It allows you to configure services to enable Internet-facing load balancing—the services then distribute incoming traffic across Azure virtual machines and balance internal loads (traffic between VMs within your VPN). 

Azure Load Balancer is a self-reconfiguring service that adjusts to the administrator’s scaling of instances. It offers monitoring capabilities and automatically ends connections to under-performing instances.

3. VPN Gateway

VPN Gateway makes it easier to encrypt connections between different premises, including secure connections from on-premises systems to your virtual network and communications between virtual networks. VPN Gateway supports various connection configurations, including inter-VNet, point-to-site, and site-to-site.

4. Azure Firewall

Azure Firewall is a managed security service for cloud-based networks. It is a stateful firewall service that can deploy on all virtual networks, filtering application-level and network traffic to protect VNet resources. Administrators can create rules to filter traffic and enforce them across multiple networks and subscriptions.

Azure Firewall provides high availability and allows you to configure the firewall to cover multiple Availability Zones (AZs) for minimal downtime. It also offers unlimited scalability in the cloud and supports automatic scaling based on changes to outbound and inbound traffic flows.

5. Azure ExpressRoute

Azure ExpressRoute lets you extend an on-premises network into the Azure cloud using a private connection from a connectivity provider. The private connection is secure because it doesn’t handle Internet traffic. ExpressRoute supports connections to various Microsoft services, including Azure, Dynamics 365, and Microsoft 365. 

6. Azure Private Link

Azure Private Link provides a private endpoint in your VNet to access your proprietary or third-party services hosted in Azure and Azure platform-as-a-service offerings, such as SQL Database and Azure Storage. Microsoft’s backbone network carries the traffic between these services and the virtual network, eliminating the need to expose your traffic to the Internet.

7. Azure Content Delivery Network (CDN)

A CDN is a distributed server network that enables the efficient delivery of web content to end-users. CDNs cache content on point-of-presence (POP) edge servers near the end-users to reduce latency.

Azure Content Delivery Network (CDN) enables you to rapidly deliver high-bandwidth content to your users in various locations globally. It leverages Microsoft’s network of strategically placed nodes in different physical locations worldwide to store content. Azure CDN also uses POPs to leverage networking optimizations and accelerate dynamic content that you cannot cache.

What Would Azure Cost You?

Azure pricing for network services differs based on the Azure resources you use, how you place them, and the communication between components in your application. It is essential to consider these charges when planning your Azure cloud usage to avoid significant surprises in your monthly bill. The larger your organization and the more sprawling deployments you have, the greater the potential for unexpected costs.

Consider that while inbound data transfers to the Azure data center are nominally free, this only applies to ingress traffic from the public Internet. It doesn’t cover different data transfer types, such as inter-region and inter-Availability Zone traffic or additional services, which all incur costs. 

The cost of data transfers in Azure differs according to the zone of origin (i.e., Zones 1, 2, and 3, US Gov, and DE Trustee). You should plan your Azure costs for network data transfers before deploying workloads. To optimize your expenses, you need to understand the multiple components involved and tweak your data flow accordingly to maximize application availability and performance while minimizing costs.

See More: What Is Microsoft Azure: Services, Certifications, and Benefits


The basics of networking in Microsoft Azure and core Azure networking services is helpful to keep in mind while considering a move to Azure:

  • Azure Virtual Network (VNet) – used to segment a cloud deployment into several secure regions.
  • Azure Load Balancer – used to balance traffic between several cloud resources.
  • VPN Gateway – used to enable secure remote access to the Azure cloud.
  • Azure Firewall – used to regulate traffic to and from Azure resources.
  • Azure ExpressRoute – lets you extend a network link from an on-premises data center to Azure.
  • Azure Private Link – a private endpoint in a VNet that connects to third-party services hosted in Azure.
  • Azure Content Delivery Network (CDN) – enables caching static content in proximity to users’ geographical location.

There is much to explore in the Azure cloud, and organizations should weigh out various networking options against their needs to make wiser decisions for their networking infrastructure.

Which Azure networking services are most beneficial to your organization? Share with us on LinkedInOpens a new window , TwitterOpens a new window , or FacebookOpens a new window . We’d love to learn from you!

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