Solution Design Document
How
This template defines the structure for a Solution Design Document (SDD). The SDD captures the use-case-specific business process, technical solution design, and architectural impact for a single use case built on top of a platform described in a Platform Architecture Document (PAD).
Instructions:
- Replace all
[bracketed placeholders]with project-specific content.- Guidance text is provided in blockquote format (lines starting with
>). Remove or replace guidance text once the section is populated.[Diagram: ...]placeholders indicate where diagrams should be inserted. Replace with the actual diagram and a brief caption. Recommended tools: draw.io, Mermaid, Lucidchart, or Visio.- Cross-references to other documents use the abbreviations PAD, OAD, and SDD followed by the section number (e.g. “refer to PAD §6.2 Network Architecture” or “see OAD §5.1 Business Process Value Stream”).
- When one use case requires multiple SDDs (e.g. distinct solution approaches), append a descriptive solution code to the filename:
PROJECT CODE – USE CASE CODE – SDD – SOLUTION CODE.md.- The Architectural Impact Assessment (§5) is the critical bridge between this SDD and the PAD. When this AIA is approved, the PAD should be updated to reflect any component changes.
Document Metadata
| Field | Detail |
|---|---|
| Initiative code | [PROJECT CODE] |
| Use case title | [Use Case Name] |
| Solution title | [Solution Name, if different from use case] |
| Document type | SDD – Solution Design Document |
| Status | [Draft / Under Review / Endorsed / Approved] |
| Author(s) | [Author Name(s)] |
| Approved by | [Approving body or individual] |
Document Version Control
This document has undergone the following document version controls:
| Date | Version | Change Description | Author |
|---|---|---|---|
| DD/MM/YYYY | 0.1 | Initial draft created | [Author Name] |
Contributors
The content of this document has been authored with the combined input of the following group of key individuals:
| Name | Role | Area |
|---|---|---|
| [Name] | Solution Lead | [Organisation] (Vendor) |
| [Name(s)] | Solution Team | [Organisation] (Vendor) |
| [Name(s)] | Business Process SME | [Business Unit] ([Client]) |
| [Name(s)] | IT Rep - Security | Information Technology ([Client]) |
| [Name(s)] | IT Rep - Architecture | Information Technology ([Client]) |
Document Approval Requirements
The following table describes the approval gates required for this document:
| Approval Gate | Status | Date |
|---|---|---|
| [Gate Name, e.g. Security Endorsement] | [Pending / Complete] | [Date] |
| [Gate Name, e.g. Architecture Peer Review] | [Pending / Complete] | [Date] |
| [Gate Name, e.g. Architecture Board Endorsement] | [Pending / Complete] | [Date] |
Related Documents
| Document | Type | Description | Link |
|---|---|---|---|
| Platform Architecture | PAD | Foundational platform infrastructure, security, networking, and operational views | [Link to PAD] |
| Opportunity Assessment | OAD | Business case and value proposition for this use case | [Link to OAD, or “N/A”] |
1 Introduction
[Provide a brief introduction explaining the purpose of this Solution Design Document. This document describes the use-case-specific solution — the business logic, technical design, and requirements for a specific use case built on top of the platform described in the PAD.]
This document is the Solution Design Document (SDD) for the [Use Case Name].
The purpose of the SDD is to:
- Provide a high-level description and diagrammatic overview of the business process
- Provide the business and technical rules and any assumptions that will govern the design and development of the solution
- Provide details of the solution design requirements and solution features
- Document the architectural impact of this use case on the platform
- Act as a reference document for manual handling operations
1.1 About Document Version
[If relevant, describe what changed in the current version of this document.]
1.2 Scope
[Define the technical scope of this solution design. This covers which technical components, integrations, and capabilities are included or excluded. Business-process scope is defined in the OAD (OAD §6 Scope). Platform boundary scope is defined in the PAD (PAD §2.3 Scope).]
| Area | In Scope | Out of Scope |
|---|---|---|
| Solution Components | [Which components are included in this design] | [Which components are excluded] |
| Integrations | [Which integrations are covered] | [Which integrations are deferred or excluded] |
| Environments | [Which environments are covered] | [Which environments are excluded] |
| Phases | [Which delivery phases are covered by this document] | [Future phases not covered] |
2 Business Process
[This section describes the business process that the solution will automate or support. For detailed background, business context, objectives, and value proposition, refer to the OAD. This section focuses on the operational detail needed to design the solution.]
2.1 Background
[Provide a brief background of the business process. If an OAD exists, reference it here and provide only a summary. If no OAD exists, provide the full business context.]
2.2 Process Description
[Describe the manual business process at a high level. List the key steps and sub-processes.]
2.3 Business Applications
[List the business applications used in this specific use case’s business process. For the full platform application inventory, refer to the PAD (PAD §3.3.3 Related Applications). Reference applications by the name used in the PAD inventory rather than re-describing them. Only add use-case-specific detail (e.g. specific API endpoints used, specific data accessed) that is not captured in the PAD.]
| Application | Role in Process | Reference |
|---|---|---|
| [App Name] | [What the app does in the context of this use case] | [Link to PAD inventory entry or external docs] |
Business Documentation:
[If there are business reference documents (e.g. work instructions, process guides, checklists) that inform this use case, list them here.]
Name Description Reference [Document Name] [What it covers] [Link or location]
2.4 Business Process Flow
[Provide detailed process flow diagrams for the business process. Use swim lanes where multiple roles are involved. Break complex processes into sub-process flows. Organise sub-sections by phase, actor, or workflow type — whichever best represents the process structure.]
[Diagram: Business process flow overview showing the end-to-end manual process with swim lanes for each role. Recommended: a BPMN-style swimlane diagram using draw.io or Mermaid.]
2.4.1 [Sub-Process 1 Name]
[Provide a detailed sub-process flow if the overall process has distinct phases.]
[Diagram: Detailed sub-process flow for [Sub-Process 1]]
2.4.2 [Sub-Process 2 Name]
[Diagram: Detailed sub-process flow for [Sub-Process 2]]
3 Solution Overview
[This section describes the technical solution for this use case. It covers what the solution does, its features, user stories, and process flows.]
3.1 Solution Description
[Provide a high-level description of the solution. What steps does it automate? What are its main components?]
Key Actors:
| Actor | Description |
|---|---|
| [Actor Name] | [What this actor does in the context of the solution] |
Solution Context Diagram:
[Diagram: Solution context diagram showing interactions between key actors, solution components, and external systems. Recommended: a C4 context diagram or UML component diagram.]
At a high level, the solution contains the following steps and related features:
- [Step 1]
- [Sub-step 1.1]
- [Sub-step 1.2]
- [Step 2]
- [Step 3]
3.2 Solution Features
[List the key features (epics) for this solution with their current status.]
| Summary | Updated | Status |
|---|---|---|
| [Feature Name] | [Date] | [Complete / In Progress / Backlog / Deferred] |
3.3 User Stories
[List all user stories for this solution, grouped by feature/epic.]
| Summary | Description | Status | Technology | Updates/Notes |
|---|---|---|---|---|
| [Epic Name] | ||||
| [Story Name] | [Description of what the user needs] | [Status] | [Technology used] | [Notes] |
3.4 Solution Process Flow
[Provide solution process flow diagrams showing how the automated solution works. Include swim lanes where applicable. Break into sub-sections for each major phase. Organise sub-sections by phase, actor, or workflow type — whichever best represents the solution structure.]
[Diagram: Solution process flow overview. Recommended: a BPMN-style or swimlane diagram showing automated and manual steps.]
3.4.1 [Phase 1 Name]
[Detailed solution process flow for this phase. Include descriptions of sub-flows if applicable.]
[Diagram: Detailed solution process flow for Phase 1]
3.4.2 [Phase 2 Name]
[Diagram: Detailed solution process flow for Phase 2]
3.5 Solution Exceptions
[Document business exceptions and system/application exceptions specific to this use case.]
3.5.1 Business Exceptions
[List business exceptions — cases where the solution cannot proceed due to business rules or data conditions.]
- [Exception 1: Description and handling approach]
- [Exception 2: Description and handling approach]
3.5.2 System/Application Exceptions
[List system or application exceptions — cases where the solution cannot proceed due to technical issues.]
- [Exception 1: Description and handling approach]
- [Exception 2: Description and handling approach]
3.6 Data Architecture
[Describe the data this solution accesses, processes, and produces. Include data flows between systems, data transformations, and any data storage specific to this use case. Reference the platform’s Information View (PAD §7) for system-of-record and governance details. Reference any Privacy Impact Assessments if applicable.]
3.6.1 Data Sources and Sinks
| Data Element | Source System | Destination | Direction | Classification | Notes |
|---|---|---|---|---|---|
| [Data Name] | [Source] | [Destination] | [Read / Write / Both] | [Classification level] | [Additional context] |
3.6.2 Data Flow
[Diagram: Data flow diagram showing how data moves through the solution. Recommended: a DFD or sequence diagram showing data transformations and storage points.]
4 Solution Component Views
[Solution Component Views provide detailed technical deep-dives for distinct features or capabilities within this use case. Each component view is a self-contained section that documents: background, feature business context, current state, solution overview, requirements, and assumptions. Structure guidance: Create one component view (§4.x) for each major feature or epic. If the solution has only one feature, use a single §4.1. If it has multiple features, repeat the §4.x structure for each. Each component view should be readable in isolation by a reviewer who needs to understand only that feature.]
[If the solution has multiple features that warrant individual deep dives, create a sub-section for each. If the solution is simple enough, this section can be replaced with a single set of requirements in section 4.1.]
4.1 Solution Component – [Feature Name]
[Repeat this structure for each major feature/component of the solution.]
Status: [WIP / Under Review / Complete / Deferred]
Impacted Components: [List of platform components impacted by this feature]
Background
[Provide contextual background for this feature. The view should be readable in isolation.]
Feature Business Context
[Describe the business context for this specific feature — process requirements, business rules, and stakeholder needs. This is feature-level context, distinct from the platform-level Business View in the PAD (PAD §2).]
Current State
[Describe the current state relevant to this feature.]
Solution Overview
[Describe how this feature works technically.]
Context Diagram
[Diagram: Context diagram for this feature]
Workflow Diagram
[Diagram: Workflow diagram for this feature]
Requirements
Functional Requirements
| Title | Description | Acceptance Criteria | Priority |
|---|---|---|---|
| [Requirement] | [Description] | [How to verify] | [High / Medium / Low] |
Non-Functional Requirements
| Title | Description | Acceptance Criteria | Priority |
|---|---|---|---|
| [Requirement] | [Description] | [How to verify] | [High / Medium / Low] |
Assumptions and Constraints
- [Assumption or constraint 1]
- [Assumption or constraint 2]
5 Architectural Impact Assessment
[The Architectural Impact Assessment (AIA) is the bridge between this SDD and the PAD. It documents what changes this use case requires to the platform, and ensures that platform impacts are reviewed by the relevant IT stakeholders.]
[When this AIA is approved, the PAD should be updated to reflect any CHANGE or NEW items, and the Use Case Register in the PAD (PAD §4) should be updated with this use case.]
5.1 Component Impact Assessment
[Document the impact of this use case on each platform component. Impact is one of: EXISTING (no change needed), CHANGE (modification required), NEW (new component needed), DECOMMISSIONED (component being removed). This table should align with the Solution Technologies table in the PAD (PAD §3.3.2). When this AIA is approved, update the PAD’s Solution Technologies table to reflect any CHANGE or NEW items, adding this use case’s ID in the ‘Source UC’ column.]
| Component | Current State in PAD | Impact | Change Description | Asset Registry ID | Lifecycle |
|---|---|---|---|---|---|
| [Component Name] | [How it currently exists in the platform] | [EXISTING / CHANGE / NEW / DECOMMISSIONED] | [What changes are needed to support this use case] | [Optional: Asset ID] | [Optional: Retain / Replace / Retire] |
5.2 Impacts to Platform Architecture Views
[Summarise how this use case impacts each horizontal view in the PAD. This table serves as a checklist to ensure all views are assessed and updated.]
| PAD View | Impact? | Summary |
|---|---|---|
| Platform Overview (PAD §3) | [YES / NO / TBC] | [Brief description of impact] |
| Integration View (PAD §5) | [YES / NO / TBC] | [e.g. “Two new interfaces required for [system] integration”] |
| Infrastructure View (PAD §6) | [YES / NO / TBC] | [e.g. “No additional infrastructure required” or “New VNet peering needed”] |
| Information View (PAD §7) | [YES / NO / TBC] | [e.g. “New data classification required for [data type]“] |
| Security View (PAD §8) | [YES / NO / TBC] | [e.g. “New user role required” or “No impacts”] |
| Support View (PAD §9) | [YES / NO / TBC] | [e.g. “Support model update needed for BAU handover”] |
| Monitoring & Observability (PAD §9.4) | [YES / NO / TBC] | [e.g. “New dashboard and alerting rules required” or “No additional monitoring needed”] |
| Capacity Planning (PAD §6.7) | [YES / NO / TBC] | [e.g. “Additional compute capacity required” or “Within current capacity”] |
5.3 Use Case Integration Interfaces
[Document the specific integration interfaces required for this use case. These are use-case-specific instances of the platform’s standard interfaces documented in the PAD’s Integration View (PAD §5.2). Reference the PAD’s interface names where applicable. Impact tracking for interfaces is managed here, not in the PAD.]
| Integration Process | Description | Interfaces |
|---|---|---|
| [Process Name] | [What this integration does for this use case] | [Initiating-system → Receiving-system | <<protocols>> | (notes)] |
5.4 Use Case Non-Functional Requirements
[Document NFRs specific to this use case that deviate from or add to the platform-wide NFR baselines defined in the PAD (PAD §9.3 Non-Functional Requirements). Do not restate baseline NFRs here — only document differences. Reference the PAD baseline by section number where applicable.]
| Requirement | Description | Acceptance Criteria |
|---|---|---|
| [NFR Name] | [Description] | [How to verify] |
5.5 Use Case Technology Choices
[Document any technologies specific to this use case that are not already part of the platform’s technology inventory. If this use case introduces a new technology, it should be assessed for addition to the PAD’s technology inventory (PAD §3.3.2 Solution Technologies).]
| Technology | Purpose | In Platform Inventory? | Notes |
|---|---|---|---|
| [Technology Name] | [Why this use case needs it] | [Yes / No — needs PAD update] | [Additional context] |
5.6 Architecture Decision Records
[Document key architecture decisions specific to this use case. Platform-wide decisions belong in the PAD’s Architecture Decision Records (PAD §3.4). If a decision made here is later recognised as having platform-wide applicability, it should be promoted to the PAD and cross-referenced here by its PAD decision ID.]
| ID | Decision | Comparison | Description | Rationale |
|---|---|---|---|---|
| SDD-ADR-01 | [Decision Title] | [Options compared] | [What was decided] | [Why this option was chosen] |
5.7 Solution Design Risks
[Identify technical and implementation risks specific to this use case’s solution design. Business risks belong in the OAD (OAD §8.1). Platform-level risks belong in the PAD (PAD §2.6 Risks). Only document risks that are unique to this solution’s technical design or implementation approach.]
| # | Risk Description | Impact | Likelihood | Mitigation | Owner |
|---|---|---|---|---|---|
| SDR-01 | [Risk description] | [Impact assessment] | [Likelihood] | [Mitigation approach] | [Who owns this risk] |
5.8 Technical Debt
[Document any technical debt being introduced by this use case’s solution. This includes workarounds, shortcuts, or deferred improvements. Once the solution is endorsed/approved, debt items should be sent to the identified owner for tracking and remediation. Platform-level technical debt belongs in the PAD (PAD §2.7).]
| # | Title | Description | Source | Owner | Date Raised | Target Resolution |
|---|---|---|---|---|---|---|
| UCDEBT-01 | [Title] | [Description of the debt] | [What caused it] | [Who owns remediation] | [Date] | [Target date or milestone] |
5.9 Test Strategy
[Describe the testing approach for this use case. Reference any separate test plan documents if they exist. This section should outline the types of testing planned, environments used, and acceptance criteria at a high level.]
| Test Type | Description | Environment | Responsible | Status |
|---|---|---|---|---|
| Unit Testing | [Approach to unit/component testing] | [Environment] | [Team] | [Planned / In Progress / Complete] |
| Integration Testing | [Approach to integration testing] | [Environment] | [Team] | [Planned / In Progress / Complete] |
| User Acceptance Testing | [Approach to UAT] | [Environment] | [Team] | [Planned / In Progress / Complete] |
| Performance Testing | [Approach to performance testing, if applicable] | [Environment] | [Team] | [Planned / In Progress / Complete] |
5.10 Deployment and Cutover
[Describe the deployment and cutover approach for this use case. This includes release planning, rollback strategy, and go-live criteria. Reference the platform’s deployment architecture in the PAD (PAD §6.1 Deployment Architecture) for environment details and deployment principles. Avoid duplicating deployment principles already documented in the PAD — focus on use-case-specific deployment considerations.]
| Aspect | Description |
|---|---|
| Deployment Approach | [How the solution will be deployed — CI/CD, manual, phased rollout, etc.] |
| Rollback Strategy | [How to revert if issues are found post-deployment] |
| Go-Live Criteria | [What conditions must be met before go-live] |
| Cutover Plan | [Steps for transitioning from current state to new solution] |
| Post-Go-Live Support | [Hyper-care or enhanced support period details] |
6 Appendix
[Use the appendix for detailed supplementary information specific to this use case — process screenshots, detailed data mappings, archived designs, etc.]
6.1 Manual Process Details
[When developing automated solutions for business processes, capture screenshots of the process being completed or video recordings. Document those details here.]
6.2 Glossary
[Define key terms, acronyms, and abbreviations specific to this use case.]
| Acronym / Term | Description |
|---|---|
| PAD | Platform Architecture Document |
| OAD | Opportunity Assessment Document |
| SDD | Solution Design Document |
| [Term] | [Definition] |
6.3 References
[List reference documents, standards, and external resources relevant to this use case.]
| # | Document / Source | Relevance |
|---|---|---|
| REF-01 | [Document name or URL] | [Why this reference is relevant] |
6.4 Archived Designs
[If any designs for this use case have been superseded, archive them here for reference.]