---
title: "Structural model vs implementation model"
subject: "Object Oriented Analysis and Design"
chapter: 1
key: "semester_6/object_oriented_analysis_and_design:structural-vs-implementation-model"
source: https://www.bctengineer.com/q/semester_6/object_oriented_analysis_and_design/structural-vs-implementation-model
site: BCT Engineering
---

# Structural model vs implementation model

Object Oriented Analysis and Design · Chapter 1: Object Oriented Fundamentals

- Asked in: 2072 Asoj, 4 marks
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/object_oriented_analysis_and_design/structural-vs-implementation-model
- Whole chapter: https://www.bctengineer.com/md/semester_6/object_oriented_analysis_and_design/chapter-1

## Question

Compare Structural Model vs. Implementation Model.

## Short answer

A structural model describes the static logical structure (classes, attributes, associations) independent of technology, using class and package diagrams. An implementation model depicts the physical realization as source code, components, and deployment nodes, using component and deployment diagrams.

## Answer

A **structural model** describes the static structure of the system: the classes, their attributes, operations and relationships, without regard to the technology used. An **implementation model** describes how the system is physically realised: source code, components, files, and the hardware/software nodes on which they run.

| Point | Structural model | Implementation model |
|---|---|---|
| Concern | Static organisation of problem and design | Physical realisation of the solution |
| Level | Analysis and logical design | Coding and deployment |
| Elements | Classes, objects, associations, packages | Source files, components, libraries, nodes |
| UML diagrams | Class, object, package diagram | Component and deployment diagram |
| Dependence on technology | Independent of language/platform | Depends on language, OS, hardware |
| Audience | Analysts, designers, customers | Programmers, system administrators |
| Example | Class `Order` with `OrderLine` (1 to many) | `order.jar` component deployed on a web server node |

```text
 Structural model:
 +-------+ 1        1..* +-----------+
 | Order |---------------| OrderLine |
 +-------+               +-----------+

 Implementation model:
 [Browser] ---- [Web Server] ---- [DB Server]
                 order.jar         orders.mdf
```

The structural model is converted step by step into the implementation model during coding and deployment.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What does a structural model describe?
   A. Static structure: classes, attributes, operations and relationships, independent of technology
   B. Source files and hardware nodes
   C. Message order only
   D. User screens only
   Answer: A. It is the logical static organisation and does not depend on technology. (Key point: Structural model)

2. Which diagrams belong to the implementation model?
   A. Class and package diagrams
   B. Component and deployment diagrams
   C. Sequence and state diagrams
   D. Use case diagrams
   Answer: B. Class/object/package diagrams are structural; component and deployment diagrams are implementation. (Key point: UML diagrams)

3. Which statement about technology dependence is correct?
   A. Structural depends on language/platform; implementation does not
   B. Structural is independent of language/platform; implementation depends on language, OS and hardware
   C. Both are independent
   D. Both depend on hardware
   Answer: B. The implementation model deals with physical realisation (e.g. order.jar on a web server). (Key point: Technology dependence)

## Related in Object Oriented Analysis and Design

- [Conceptual, specification, implementation model classification](https://www.bctengineer.com/question.md?key=semester_6%2Fobject_oriented_analysis_and_design%3Ahospital-conceptual-specification-implementation) — Object Oriented Analysis and Design, chapter 2
- [Interface vs implementation](https://www.bctengineer.com/question.md?key=semester_6%2Fobject_oriented_analysis_and_design%3Ainterface-vs-implementation) — Object Oriented Analysis and Design, chapter 4, asked 2×
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- [Flowchart vs structure chart](https://www.bctengineer.com/question.md?key=semester_6%2Fobject_oriented_analysis_and_design%3Aflowchart-vs-structure-chart) — Object Oriented Analysis and Design, chapter 1

## Related in other subjects

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