Foundational Knowledge

Introductory chapter: how networks, OS and hardware influence architectural decisions.

Basic computer architecture: abstraction layers, ISA, memory, input/output and interaction with the OS.

Comparison of architecture and workload types: CPU versatility versus GPU parallelism.

The difference between RAM and HDD/SSD, speed, latency and storage cost.

Processes and threads, scheduling, memory, file systems, virtualization and security.

User space and kernel space, the role of the kernel and drivers, common operating systems and their scenarios.

Why Linux became the standard for servers, its basic architecture and role in system design.

Analysis of the evolution of Unix-like systems: from Bell Labs and standardization to Linux, BSD, Darwin and Android.

Android architecture, difference from Linux, limitations and capabilities of mobile devices.

Types of virtualization, hypervisors and practical design of virtual machines.

How containers are structured, layered file system, cgroups/limits and comparison with VM.

Network models, protocols, routing, reliability, security and wireless networks.

Tanenbaum's classic textbook: layers, protocols, routing, security and network applications.

Seven layers of the network, a visual map and the reasons why TCP/IP turned out to be more practical.

The essence of IPv4/IPv6, key differences, risks and practical path of migration to IPv6.

Reliable byte delivery: connection, three‑way handshake, flow and congestion control.

Lightweight connectionless protocol: low latency, minimal overhead and speed.

DNS server hierarchy, zones and delegation, caching and resolution process.

Basic web protocol: request-response, key properties and evolution to HTTP/2 and HTTP/3.

Duplex channel over HTTP Upgrade: connection establishment and real-time messaging.