Architectural Thinking and Multi‑Layered Cloud, SOA, and Application Architecture

Architecture Thinking Overview

Architecture thinking is a collection of system, structured, and programming mindsets that bridges real‑world business and abstract IT implementation; its core is business‑driven technology, requiring a balance of requirements, implementation, software, hardware, static and dynamic aspects, cost and benefit.

Two key focuses in architecture design are decomposition and integration. Decomposition breaks complex problems into cohesive, loosely‑coupled parts while defining the problem; integration then assembles those parts through appropriate interfaces to form a complete whole.

Cloud Platform Three‑Layer Architecture: Resource‑Platform‑Application

The standard cloud three‑layer model consists of IaaS (infrastructure), PaaS (platform services), and SaaS (applications). The resource layer spans physical to virtual resources (including containers). The platform layer now includes both technical and business platforms (often called the middle‑platform). A service layer sits between platform and application to decouple resources from services.

For IoT scenarios, additional network and perception layers are added beneath the resource layer, as shown in typical smart‑city platform diagrams.

Question 1: Database and Data Layer

In a complete enterprise architecture there is no separate “data layer”; data concerns appear only within individual application architectures or technical architectures where databases, middleware, etc., are represented.

Question 2: Service Layer and Services

A dedicated service layer can be exposed as an open‑platform without enumerating specific business services; it essentially represents the middle‑platform (or “mid‑platform”) that provides capability APIs.

SOA Layering: Component‑Service‑Process

SOA emphasizes a distinct service layer that abstracts resources as APIs. A typical SOA diagram shows components, service domains, and processes, with the data layer replaced by a component layer.

Cloud and SOA Architecture Fusion

The fusion model combines cloud’s three layers (resource‑service‑application) with SOA’s three layers (component‑service‑application). For example, the IaaS resource layer provides APIs (service layer) that together form a public‑cloud SaaS offering.

Application Architecture Layering

The classic three‑tier architecture consists of User Interface, Business Logic (Domain), and Data Access (Infrastructure) layers. Domain‑Driven Design adds an Application layer between UI and Domain, and renames Business Logic to Domain and Data Access to Infrastructure.

Domain models represent business objects; services expose domain capabilities. An additional Application layer can orchestrate multiple domain services for reuse across different front‑ends (e.g., mobile app, web portal).

Software Technical Architecture Layering

Technical architecture also follows a three‑tier model, focusing on key technology components (e.g., messaging middleware like RabbitMQ, big‑data pipelines, etc.) rather than business functions.

Single Application Function Architecture

Function architecture describes what capabilities an application provides, typically using a three‑layer view: foundational support layer, execution layer, and decision‑management layer, or alternatively support‑application‑portal layers.

Architecture Diagram Layering Logic

When drawing an overall architecture diagram, reference cloud three‑layer and SOA three‑layer patterns for the central part, while standards, security, quality, and operational guidelines occupy the sides. The central part usually consists of resource, platform, service, and application layers, with the service layer acting as the glue.

Different stakeholders (business users, developers, operations) use different views of the same layered architecture.

#IDCF DevOps Hackathon Challenge

The article concludes with a promotion for the IDCF DevOps Hackathon (Sept 17‑18, 2022, Beijing), inviting teams and individuals to build a product from 0 to 1 in 36 hours.