Networking Across the Three Clouds

Private networks, DNS, load balancers, CDNs, dedicated lines — every cloud offers all of them. The concepts are identical. What varies is the name each provider chose for the same building block. Those naming differences trip up beginners more than the concepts themselves do.

This topic is a reference map: take each networking idea from this chapter and see what AWS, Google Cloud, and Azure call it. One read through this alignment is enough to make any provider's networking documentation readable.

One genuine difference is worth knowing: on Azure, load balancing is split across two products depending on what layer of traffic you're handling. That distinction is real and explained below — everything else is just a name.

The Mapping

Start with the private network. AWS and Google Cloud both call it a VPC — Virtual Private Cloud. Azure calls the same thing a Virtual Network, shortened to VNet. Same concept: your isolated slice of the provider's network where your resources live and communicate privately. The rows below map the rest.

The One Real Naming Quirk: Azure Load Balancing

Most name differences in cloud networking are cosmetic — the same idea, different words. Azure's load balancing is a genuine split worth understanding. Azure has two products:

Azure Load Balancer operates at the network layer (Layer 4). It distributes traffic based on IP addresses and ports, without inspecting the content of the request. It's fast and handles raw TCP/UDP traffic — roughly equivalent to the most basic mode of AWS Elastic Load Balancing.

Azure Application Gateway operates at the application layer (Layer 7). It can inspect the content of HTTP requests — routing by URL path, handling SSL termination, applying rules based on request headers. This is the product that maps to AWS's Application Load Balancer (ALB). When people say "application-level load balancing" on Azure, they mean Application Gateway.

AWS, by contrast, packages its layer-4 and layer-7 load balancers under the same Elastic Load Balancing (ELB) umbrella, so the distinction is internal. Google Cloud Load Balancing similarly covers both modes. Only Azure names them as separate services.

The Constants

Behind every name change, the purposes are identical. Every cloud gives you: a private network to isolate resources; a managed DNS service to name them; a load balancer to spread incoming traffic; a CDN to cache content near users; and a dedicated line option to bypass the public internet when you need a private, predictable connection. The vocabulary differs; the architecture does not.

Reading an Architecture Diagram

When you look at an architecture diagram from any of the three clouds, the networking layer always assembles the same pieces. There is a private network containing servers and databases. Something at the edge — a load balancer, an Application Gateway — receives incoming requests. A CDN may sit in front of the whole thing. DNS routes users to the right entry point. A VPN or dedicated line may connect the cloud network to an on-premises building. Once you know what each piece does, you can read any diagram regardless of which provider it depicts.