Intermediate|13 hours|32 lessons

Networking and API Design for System Design

The communication layer of system design. Networking fundamentals, API design (REST, GraphQL, gRPC), API infrastructure, API security, and real-time and asynchronous communication patterns. Built for senior engineers who need to reason about how distributed systems communicate, in interviews and in production.

Text-based, no videos

5 modules, 32 lessons

Lifetime access

What you'll learn

The network stack beneath every design: the OSI layers, IP addressing and NAT, TCP versus UDP, and where latency actually comes from

HTTP in depth for system design: methods and status codes, HTTP/1.1 versus HTTP/2 versus HTTP/3, connection reuse, and how HTTPS secures the path

DNS as an architectural tool: resolution, caching and TTLs, and its use and limits as a global load balancing and failover mechanism

API contracts that survive: versioning without breaking clients, backward compatibility, and idempotency for safe retries

Choosing an API style with reasons: REST, GraphQL, and gRPC compared on performance, caching, tooling, and consumer fit

The infrastructure in front of your services: API gateway responsibilities, and rate limiting algorithms that hold up across a distributed fleet

API security at the design level: authentication versus authorization, sessions versus tokens, JWTs, OAuth2, and SSO

Real-time communication and how it scales: long polling, WebSockets, SSE, webhooks, and WebRTC

Asynchronous architecture: message queues, pub/sub, change data capture, delivery semantics, and dead letter queues

Interview-ready reasoning: every lesson ends with a system design interview question on the concept it teaches

Curriculum

5 modules · 32 lessons

Networking

The network layer beneath every system you design: the OSI model, addressing, transport protocols, HTTP, DNS, data integrity, and proxies.

7 lessons

OSI Model25 minFREE IP Address25 minFREE TCP vs UDP25 minFREE HTTP/HTTPS25 minFREE Domain Name System (DNS)25 minFREE Checksums25 minFREE Proxy vs Reverse Proxy25 minFREE

API Design

Designing the contract: versioning and compatibility, idempotency, data formats, and the major API styles (REST, GraphQL, gRPC) in depth.

7 lessons

What is an API?25 min Idempotency25 min Data Formats25 min API Architectural Styles25 min REST API Design25 min GraphQL Deep Dive25 min gRPC Deep Dive25 min

API Infrastructure

The layer that fronts your services: API gateways as a single entry point, and rate limiting to protect what sits behind them.

2 lessons

API Gateways25 min Rate Limiting25 min

API Security

Securing the API surface at the system design level: authentication versus authorization, sessions versus tokens, JWTs, OAuth2, and SSO.

5 lessons

Authentication vs Authorization25 min Session vs Token Based Auth25 min JWT25 min OAuth / OAuth225 min Single Sign-On (SSO)25 min

Communication Patterns

How systems talk when request-response is not enough: real-time transports (long polling, WebSockets, SSE, webhooks, WebRTC) and asynchronous messaging (queues, pub/sub, CDC, delivery semantics, dead letter queues).

11 lessons

Long Polling25 min WebSockets25 min Server-Sent Events (SSE)25 min Webhooks25 min WebRTC25 min Sync vs Async Communication25 min Message Queues25 min Pub/Sub25 min Change Data Capture (CDC)25 min Delivery Semantics25 min Dead Letter Queues25 min

About the Author

Sharon Sahadevan

AI Infrastructure Engineer

Building production GPU clusters on Kubernetes. H100s, large-scale model serving, and end-to-end ML infrastructure across Azure and AWS.

10+ years designing cloud-native platforms with deep expertise in Kubernetes orchestration, GitOps (Argo CD), Terraform, and MLOps pipelines for LLM deployment.

Author of KubeNatives, a weekly newsletter read by 3,000+ DevOps and ML engineers for production insights on K8s internals, GPU scheduling, and model-serving patterns.

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