Communication Patterns
Patterns for information exchange between components, services, and teams; describes models, protocols and integration strategies.
Classification
- ComplexityMedium
- Impact areaTechnical
- Decision typeArchitectural
- Organizational maturityIntermediate
Technical context
Principles & goals
Use cases & scenarios
Compromises
- Hidden dependencies via uncontrolled topics
- Data inconsistencies without compensation logic
- Broker overload or bottlenecks due to wrong topology
- Use schema registries for compatibility control
- Define clear versioning and migration strategies
- Instrument communication comprehensively for tracing
I/O & resources
- Architecture and domain understanding
- Definition of message formats and contracts
- Platform for messaging or streaming
- Established communication patterns and guidelines
- Implemented integration paths with monitoring
- Documented error and recovery strategies
Description
Communication patterns describe recurring ways and protocols by which components, services, or teams exchange information. They cover synchronous and asynchronous models, message formats, error handling and consistency strategies. Understanding these patterns reduces coupling, improves scalability and helps manage integration risks. Practical patterns include pub/sub, request-reply and event sourcing.
✔Benefits
- Reduced coupling and improved scalability
- Clearer separation of responsibilities
- Better observability and traceability
✖Limitations
- Increased complexity with asynchrony and error handling
- Not all problems suit pure event models
- Requires clear contracts and governance
Trade-offs
Metrics
- Message throughput
Number of messages processed per second; indicator of performance.
- End-to-end latency
Time between event creation and processing; important for responsiveness.
- Error rate / dead-letter rate
Share of failed messages and overflow into dead-letter queues.
Examples & implementations
E-commerce order process (event-driven)
Orders produce events that loosely couple inventory, billing and shipping.
Internal API gateway (request/reply)
Secure synchronous API calls with consistent contracts and timeouts.
Monitoring pipeline (observability)
Metrics and events are streamed and centrally analyzed to reconstruct communication traces.
Implementation steps
Analyze existing communication paths and identify bottlenecks
Select appropriate patterns (e.g. pub/sub, request/reply, event sourcing)
Define schemas, contracts and SLAs
Introduce iteratively with monitoring and feedback loops
⚠️ Technical debt & bottlenecks
Technical debt
- Ad-hoc topics without naming conventions
- Missing schema registry indexing
- Insufficient observability on integration paths
Known bottlenecks
Misuse examples
- Using events as a substitute for missing business rules
- Switching all interfaces to async at once without tests
- Omitting monitoring and discovering issues only in production
Typical traps
- Assuming asynchrony automatically solves scalability
- Underestimating data consistency requirements
- Missing governance for message formats
Required skills
Architectural drivers
Constraints
- • Existing legacy interfaces constrain migrations
- • Regulatory requirements for data storage
- • Budget for messaging infrastructure