Distributed Systems — Episode 2

The second episode separates software from system architecture: components and connections versus placement on nodes. A layered style improves replacement and testing, but boundaries add transformation and latency. A distributed object hides the network interface without removing network semantics.

REST appears as a resource-oriented style, while microservices are logical and transactional boundaries. Event-based architecture removes direct spatial coupling. Topic-based and content-based subscriptions determine event recipients in different ways.

Interceptors, wrappers, and adapters extend middleware without rewriting applications. Multi-tier client–server designs are compared with peer-to-peer networks. Structured P2P maintains topology for lookup; unstructured P2P permits free joining and pays for dissemination.

Cloud combines resource pooling, elasticity, and service layers while demanding scrutiny of cost, guarantees, and lock-in. Edge moves processing toward the source for latency. Blockchain closes the survey as a distributed ledger whose architecture follows validation and agreement rules rather than hype.