Is this a video course?

No. This is an interactive, slide-based learning platform. Each lesson has rich text, animated diagrams, live code editors, and quizzes. You learn by reading, interacting, and doing, not by watching videos passively.

How long do I have access?

Forever. Both pricing tiers are one-time payments with lifetime access. This includes all current 766 lessons and any future content we add.

What level of experience do I need?

None. We start from absolute basics like 'What is latency?' and build up to distributed consensus protocols. The Foundation level assumes zero prior knowledge of system design.

How much does the system design course cost?

7.99 US dollars for lifetime access globally, or 499 Indian rupees for lifetime access in India. One-time payment, no subscription, no hidden fees. 11 lessons are free with no signup required.

What technologies are covered?

Everything from DNS and load balancers to Kubernetes, Kafka, distributed databases, consensus protocols, stream processing, security architecture, and observability. We cover principles and real-world implementations used at Netflix, Google, Amazon, Uber, Stripe, and more.

Is this useful for system design interview preparation?

Yes. The lessons are structured around the exact topics asked in system design interviews at FAANG and top-tier companies. Interactive diagrams help you practice whiteboard-style explanations. Covers everything from URL shortener design to distributed payment systems.

How is this different from ByteByteGo or Educative?

766 interactive lessons (4x more than most competitors), 16 different diagram types that build step by step, real production examples from Netflix, Google, Amazon, Uber, and Stripe, and lifetime access for a one-time payment of $7.99 instead of annual subscriptions costing 100 to 200 dollars per year.

What overhead does keep-alive eliminate?

TCP and TLS handshake overhead for subsequent requests on the same connection, Keep-alive reuses the TCP connection (and its TLS session) across multiple requests. This skips the 1-3 round trips needed for TCP and TLS handshakes on every subsequent request. Server-side processing and header parsing still happen on every request.

10,000 mobile clients each maintain a keep-alive connection to your server, but most are idle. What is the risk?

The server exhausts file descriptors and memory holding 10,000 idle connections, Each open TCP connection consumes a file descriptor and a small amount of memory on the server. 10,000 idle connections waste these resources. Set an idle timeout (e.g., 30 seconds) so connections that are not being used get closed, freeing resources for active clients.

Node.js defaults to keepAliveTimeout = 5000ms. Nginx defaults to keepalive_timeout 75s. What happens if you put Node.js behind Nginx without adjusting either?

Node.js closes the connection after 5 seconds. Nginx tries to reuse it and gets ECONNRESET., The server (Node.js) closes the connection after 5 seconds of idle time. The reverse proxy (Nginx) still considers it alive for 75 seconds and tries to send a request on the dead connection. The fix: set the Node.js keepAliveTimeout higher than the Nginx keepalive_timeout, or set the Nginx timeout lower.

Keep-Alive Connections

Name: System Design Masterclass
Availability: InStock

in Api Design Protocols

This lesson is part of the full System Design Masterclass. Unlock it along with 765 other lessons for a one-time payment.

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