01 Services
Terminology
| Term | Description |
|---|---|
| Region | An area where data is stored. Data storage in a Region closest to you is one of the reasons it can be accessed at lightning speed. |
| Availability Zone | One or more data centers that house many servers. Each Region has multiple, isolated locations known as Availability Zones. |
| Edge Location | A site where data can be stored for lower latency. Often, edge locations will be close to high-population areas that will generate high traffic volumes. |
| Latency | The delay before a transfer of data begins after the data has been requested. |
Cloud Data Centers
Cloud data centers can be classified into four tiers. The classification is based on the uptime and redundancy of the data center (source Uptime Institute).
| Tier 1 | Tier 2 | Tier 3 | Tier 4 | |
|---|---|---|---|---|
| Uptime Guarantee | 99.671% | 99.741% | 99.982% | 99.995% |
| Downtime per year | < 28.8 hours | < 22 hours | < 1.6 hours | < 26.3 minutes |
| Redundancy | None | partial N+1 | full N+1 | 2N or 2N+1 |
| Concurrently Maintainable | No | No | Yes | Yes |
| Fault Tolerance | No | No | No | Yes |
| Compartmentalization | No | No | No | Yes |
| Continuous Cooling | No | No | No | Yes |
Infrastructure
Regions and Availability Zones are the building blocks of large cloud providers. Regions are separate geographic ares, where data centers are located. Each region has multiple Availability Zones, which are isolated locations with their own power, cooling, and networking. Availability Zones are connected to each other, providing low-latency redundancy between them.
Azure also has the concept of Region Pairs which are geographically separated regions which are paired together for disaster recovery purposes. In case of a disaster in one region, the paired region can take over the services.
Azure and AWS Services
Azure and AWS offer a wide range of services.
| Type | Description | Azure | AWS |
|---|---|---|---|
| Virtual Machines | Virtual machines that can run any operating system | Azure Virtual Machines | Amazon EC2 |
| Storage | Storage attachable to virtual machines | Azure Disks | Amazon EBS |
| Storage | Object storage | Azure Blob Storage | Amazon S3 |
| Serverless | Serverless computing | Azure Functions | AWS Lambda |
| Container | Kubernetes Cluster | Azure AKS | Amazon EKS |
| Database | Relational database | Azure SQL/Postgres/MySQL Database | Amazon RDS/Aurora |