Microservicios

From Monolith to Microservices

A monolithic application packages all business logic into a single deployable unit. As the codebase grows, a small change requires redeploying the entire application — increasing release risk and slowing teams. Microservices decompose the system into small, independently deployable services, each owning a bounded domain context and communicating over REST APIRepresentational State Transfer Application Programming Interface. An architectural style for web services that uses standard HTTP methods (GET, POST, PUT, DELETE) and stateless communication to manipulate resources identified by URLs., GraphQLA query language and runtime for APIs developed by Meta that allows clients to request exactly the data they need in a single request. Unlike REST, GraphQL uses a single endpoint with a typed schema., or gRPCA high-performance, open-source RPC framework developed by Google that uses Protocol Buffers for serialization and HTTP/2 for transport. Supports bidirectional streaming and is widely used in microservice architectures. interfaces.

Network Implications

Where a monolith makes in-process function calls, microservices make network calls — introducing LatencyThe time delay for a data packet to travel from source to destination, typically measured in milliseconds (ms). Lower latency is critical for real-time applications like video calls, gaming, and financial trading., Packet LossThe percentage of data packets that fail to reach their destination, typically caused by network congestion, faulty hardware, or wireless interference. Even 1-2% packet loss can noticeably degrade voice and video quality. risk, and serialization overhead. Service discovery, Load BalancerA device or service that distributes incoming network traffic across multiple backend servers to ensure no single server is overwhelmed. Improves availability, reliability, and scalability of web applications. configuration, and circuit breakers become essential infrastructure. An API GatewayA server that acts as a single entry point for multiple backend microservices, handling request routing, rate limiting, authentication, and protocol translation. Examples include Kong, AWS API Gateway, and Nginx. handles the external surface, while internal service-to-service communication often travels over a service mesh with mutual SSL/TLSSecure Sockets Layer / Transport Layer Security. Cryptographic protocols that provide encrypted, authenticated communication over a network. SSL is deprecated; modern implementations use TLS 1.2 or TLS 1.3. (mTLS) between pods.

Operational Complexity

Microservices trade deployment simplicity for scalability and team autonomy. Each service can scale independently — a payment service under high load scales without touching the user profile service. But distributed tracing, SyslogA standard protocol (RFC 5424) for transmitting log messages from network devices, servers, and applications to a central log collector. Syslog messages include severity levels from emergency (0) to debug (7). aggregation across dozens of services, and SNMP TrapAn unsolicited notification sent by an SNMP agent on a network device to a management station when a significant event occurs (e.g., link down, high CPU). Unlike SNMP polling, traps provide immediate event-driven alerts. alerts require mature observability tooling. NetFlowA Cisco-developed protocol that collects metadata about IP network traffic flows (source/destination IP, ports, protocol, byte count) for analysis. NetFlow data is essential for bandwidth monitoring, capacity planning, and security forensics. analysis helps identify unexpected inter-service communication patterns that may indicate misconfiguration or a security incident. Containerization (Docker) and orchestration (Kubernetes) are common prerequisites for making microservices operationally viable at scale.