SQL Azure Architecture Overview

Continuing the theme of Windows Azure posts let's take a look the SQL Azure architecture.

Meat & Potatoes

There's four layers that comprises SQL Azure:

1. Client Layer
2. Services Layer
3. Platform Layer
4. Infrastructure Layer

Client Layer

The client layer is closest to your application. This can be on the ground or in the cloud. Here you still have access to your favorite tools and libraries you use when building applications.

Services Layer

The services layer is the parkway to get from the client layer to the next layer, the platform layer. It serves these purposes: provisioning, billing/metering, and connection routing.

The services layer handles the provisioning of the database instances that you specify thru your Windows Azure account. Billing and metering is the money mechanism and determines what your usage and billing amount will be for the period. Connection routing is what keeps your application connected to everything as you scale, etc.

Platform Layer

The platform layer is the physical layer of the servers and services that support the aforementioned services layer. This is all managed thru the SQL Azure fabric. Think of the fabric as the components that make up your ground infrastructure (failover, load balancing, etc.).

Infrastructure Layer

The infrastructure layer is all the fun of administering the physical hardware and operating systems of the services layer.

Mongo Sez (Summary)

1. Four layers of SQL Azure: Client, Services, Platform, and Infrastructure.
2. Client: Closest to your application and your everyday tools and libraries.
3. Services: Provisioning, Billing/Metering, and Connection Routing.
4. Platform: Physical layer of servers and services managed thru SQL Azure fabric.
5. Infrastructure: Administration of physical hardware and operating systems.
6. Image source and detailed overview of SQL Azure architecture: MSDN Reference
7. Also check the SQL Azure General Guidelines and Limitations on MSDN.