Domain
A domain is a subject area or problem context with relevant concepts, rules, activities, and terminology that software represents or supports.
Architecture Modernization: Socio-technical alignment of software, strategy, and structure
A bounded area of business knowledge, activity, and responsibility that groups related subdomains and supports shared higher-level purposes.
- How it is used
- Groups related subdomains and value streams around higher-level business outcomes to guide team alignment and architectural boundaries.
- How deep it goes
- Defines domains, illustrates nested scopes, and develops collaborative boundary discovery; stops short of prescribing one decomposition for every organization.
- Examples
- Uses fulfillment subdomains, an airline decomposition, EventStorm timelines, and financial accounts to make boundaries concrete.
- What you can do after
- Practice/perform collaborative domain mapping and evaluate candidate boundaries against cohesion, ownership, dependencies, and business outcomes.
Acing the CCNA Exam: Volume 2 Advanced Networking and Security
A domain is a subtree of the DNS hierarchy under the administrative control of an organization or individual.
- How it is used
- Organizes DNS names into administratively controlled subtrees for translating host names into IP addresses.
- How deep it goes
- Defines hierarchy, naming terminology, and www conventions, without detailing domain administration procedures.
- Examples
- Uses the root domain, com, google.com, www.google.com, and a Google Maps URL to illustrate hierarchy and resolution.
- What you can do after
- Evaluate DNS names by identifying their hierarchy, qualification level, URL authority, and role in name resolution.
Read how Acing the CCNA Exam: Volume 2 Advanced Networking and Security explains domain →
Building User-Friendly DSLs
A bounded area of knowledge, activity, or business concern that a software system addresses.
- How it is used
- Frames the business knowledge that a DSL, Domain IDE, and Runtime are built to represent and support.
- How deep it goes
- Defines domains, domain experts, and business domains, then identifies criteria for applying a DSL-based approach.
- Examples
- Uses car rental, price quotes, rental pricing, regulatory compliance, eligibility rules, and customer-history discounts.
- What you can do after
- Evaluate whether a business domain has sufficient structure and complexity to justify a DSL-based approach.
Google Anthos in Action
A business domain is a bounded area of business knowledge, rules, data, and capabilities addressed by software.
- How it is used
- Uses business domains to decompose legacy applications into independently developed services during modernization.
- How deep it goes
- Explains isolation, service contracts, incremental extraction, and rewrite trade-offs without detailing domain-modeling techniques.
- Examples
- Uses authentication, authorization, and logging as capabilities that can be extracted first from a legacy application.
- What you can do after
- Apply it by isolating and extracting a business capability into a service with a stable contract.
Effective Platform Engineering
A domain is a distinct area of business or user capability with its own concepts, responsibilities, and boundaries.
- How it is used
- Organizes engineering-platform responsibilities around user experience, independent team ownership, and manageable dependencies.
- How deep it goes
- Defines boundary criteria, coordination patterns, warning signals, and assessment attributes without detailing individual domain implementations.
- Examples
- Uses platform-domain dependency diagrams, independent team backlogs, and recurring cross-team Slack, email, or meeting requests as examples.
- What you can do after
- Evaluate domain boundaries by examining coupling, coordination paths, change ownership, release independence, and user experience.
Related concepts
- subdomainhas part · A subdomain is a bounded subdivision or subordinate namespace within a broader domain, such as a business area or a domain-name hierarchy.
- DNS hierarchypart of · A DNS hierarchy is the layered organization of DNS servers and domains from the root through top-level domains to specific domains.
- originpart of · A web origin is the security identity defined by a resource's scheme, host, and port.
- implementationcontrasts with · An implementation is the concrete code, mechanisms, or artifacts that realize an abstract design, specification, algorithm, interface, or required behavior.
- IP addresscontrasts with · An IP address is a numerical address used by the Internet Protocol to identify a network interface and support packet delivery across networks.
- performancemeasured by · Performance is the measurable effectiveness or operational behavior of a system under specified conditions, assessed through relevant qualities such as task results, speed, responsiveness, throughput, or resource use.
These guides are generated from the text of Manning books by Manning's knowledge graph and link to the sections they draw on. The full books are available on liveBook and at manning.com.