12.2 Building Blocks: ABBs & SBBs
Key Takeaways
- TOGAF defines a building block as a potentially re-usable component that can be combined with other building blocks to deliver architectures and solutions.
- An Architecture Building Block specifies the required Solution Building Blocks at a more logical, supplier-independent level.
- A Solution Building Block is a physical or implementation-specific component that realizes part or all of one or more logical Architecture Building Blocks.
- ABBs relate to the Architecture Continuum, while SBBs relate to the Solutions Continuum.
- ABBs are defined in Phases B, C, and D, and candidate SBBs are identified and grouped into work packages in Phase E.
Last updated: September 2026
12.2 Building Blocks: ABBs & SBBs
The Foundation syllabus asks you to explain what building blocks are and their use in the ADM. Building blocks are the re-usable components that architectures and solutions are assembled from, and the ABB/SBB distinction mirrors the move from architecture to implementation.
Definitions
| Term | TOGAF Standard, 10th Edition definition |
|---|---|
| Building Block | A potentially re-usable component that can be combined with other building blocks to deliver architectures and solutions |
| Architecture Building Block (ABB) | An architectural component that specifies the required Solution Building Blocks at a more logical, or supplier-independent, level |
| Solution Building Block (SBB) | A physical or implementation-specific component that realizes part or all of one or more logical ABBs. There are business, application, and technology SBBs |
Building blocks can be defined at various levels of detail, depending on the stage of architecture development. At an early stage, a building block can consist of just a name or an outline description; later it may be decomposed into multiple supporting building blocks with a full specification.
Characteristics of Building Blocks
A building block:
- Is a package of functionality defined to meet the business needs across an organization
- Has a type that corresponds to the enterprise metamodel (such as actor, business service, application, or data entity)
- Has a defined boundary and is generally recognizable as "a thing" by domain experts
- May interoperate with other, interdependent building blocks
A good building block also:
- Considers implementation and usage, and evolves to exploit technology and standards
- May be assembled from other building blocks, or be a subassembly of other building blocks
- Is ideally re-usable and replaceable, and well specified
ABBs Versus SBBs
| Aspect | Architecture Building Blocks (ABBs) | Solution Building Blocks (SBBs) |
|---|---|---|
| Purpose | Capture architecture requirements (business, data, application, and technology requirements); direct and guide the development of SBBs | Define what products and components will implement the functionality; define the implementation; fulfil business requirements |
| Nature | Logical, supplier-independent | Physical, implementation-specific; product or vendor-aware |
| Continuum | Relate to the Architecture Continuum | Relate to the Solutions Continuum |
| Typical specification content | Fundamental functionality and attributes (including security and manageability); interfaces; interoperability and relationships with other building blocks; dependent building blocks; mapping to business and organizational entities and policies | Specific functionality and attributes; implemented interfaces; required SBBs and interfaces used; mapping to IT topology and operational policies; shared attributes such as security, manageability, scalability; performance and configurability; design drivers and constraints; relationships to ABBs |
The Core Concepts chapter gives a simple example: a customer services capability may be required within an enterprise (an ABB describing required capability), supported by many SBBs, such as processes, data, and application software.
Building Blocks and the ADM
| ADM stage | Building block activity |
|---|---|
| Phase A | Building blocks are identified at a high level in the Architecture Vision |
| Phases B, C, D | Architecture Building Blocks are defined for each domain; gap analysis compares baseline and target ABBs |
| Phase E | Candidate Solution Building Blocks are identified and grouped into work packages, classified as new development, purchased, or re-used |
| Phase F | Work packages containing SBBs are prioritized and scheduled; re-usable ABBs are recorded |
| Phase G | SBBs are implemented under Architecture Contracts and checked through compliance reviews |
| Architecture Repository | ABBs and SBBs are stored and classified for re-use across ADM cycles |
Structural Cardinality: Mapping ABBs to SBBs
The mapping between ABBs and SBBs is often not a simple 1:1 relationship:
- 1-to-Many: A single logical ABB may require multiple physical SBBs (e.g., a Disaster Recovery Storage ABB realized by AWS S3, CloudFront CDN, and Glacier).
- Many-to-1: A single COTS SBB frequently realizes dozens of ABBs (e.g., SAP S/4HANA realizing ABBs across ledger, billing, and contact management).
Worked Enterprise Examples Across Architecture Domains
| Domain | Requirement | Architecture Building Block (ABB) [WHAT] | Candidate Solution Building Blocks (SBBs) [HOW] | Selected Realization |
|---|---|---|---|---|
| Business | Identity verification of banking applicants. | Customer Identity Verification Service: Photo ID check in <2s. | Trulioo API, Jumio Verification, Onfido. | Jumio Biometric SaaS |
| Data | Unified analytical customer profile. | Master Customer Analytical Data Store: ACID, petabyte SQL. | Snowflake Data Cloud, BigQuery, Redshift. | Snowflake Data Cloud |
| Application | Asynchronous order checkout orchestration. | Publish-Subscribe Message Bus: Event streams, 100k msgs/sec. | Apache Kafka, RabbitMQ, AWS SNS/SQS. | Confluent Cloud Kafka |
| Technology | Hosting platform for containerized services. | Container Orchestration Engine: Pod auto-scaling, mTLS. | Amazon EKS, Red Hat OpenShift, Google GKE. | Amazon EKS with Istio |
Common Exam Pitfalls
- Naming vendor products in ABBs. ABBs are supplier-independent; product-aware components are SBBs.
- Assuming a one-to-one mapping. One SBB can realize several ABBs, and one ABB can need several SBBs.
- Confusing building blocks with deliverables. Building blocks are re-usable components; deliverables are signed-off work products that describe them.
- Reversing the continua. ABBs relate to the Architecture Continuum; SBBs relate to the Solutions Continuum.
Loading diagram...
Test Your Knowledge
How does the TOGAF Standard, 10th Edition define an Architecture Building Block?
A
B
C
D
Test Your Knowledge
Which statement describes Solution Building Blocks?
A
B
C
D
Test Your Knowledge
In which ADM phase are candidate Solution Building Blocks identified and grouped into work packages?
A
B
C
D
Test Your Knowledge
Which of the following is a characteristic of a good building block?
A
B
C
D