97 Things Every Cloud Engineer Should Know

Chapter 11. Don’t Think of Services, Think of Capabilities

Haishi Bai

Principal Software Architect at Microsoft

Acquiring a continuous power supply is a fundamental capability of a mobile device. Most of us are familiar with sight of people flocking around charging stations at airports (before the pandemic happened). As a matter of fact, because this capability is so critical, we use a mixture of methods to provide a continuous power supply to our precious phones—integrated batteries (in a software sense, in-process libraries), portable power banks (local Docker containers or services), or power plugs (service-oriented architecture, or SOA).

To get your phone working, you don’t really care whether the power comes from a plug or a power bank; you just need the capability to acquire power. Capability-oriented architecture (COA) aims to provide a set of languages and tools for developers and architects to design applications based on capabilities, regardless of where and how these capabilities are delivered, which is an operational concern.

COA is especially relevant to edge-computing scenarios. For an edge solution to keep continuous operation, it often needs to switch between service providers when network conditions change. For example, a smart streetlight system sends high-resolution pictures to a cloud-based AI model to detect wheelchairs on a crosswalk and extends the green ...