deep-roots learning program · module 13
Module 13 — Networking internals
Every chapter: first principles, What insiders know, a See it yourself lab, connections, and a quiz with worked answers.
01
Wire, NIC, and the DMA ring
Encoding, the Ethernet frame, and the descriptor ring — packets land in RAM before the CPU knows.
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02
The kernel packet path
`sk_buff` anatomy, netfilter/conntrack, qdisc, XDP — the receive path as a memory story.
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03
TCP: the buffer machine
Flow control, congestion control, BDP arithmetic, bufferbloat — windows are buffers.
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04
Userspace I/O: read, epoll, io_uring
The copy ladder, the ready list, shared-memory rings — eliminating syscalls one by one.
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05
QUIC, RDMA, and the network as memory
TCP rebuilt in userspace; memory registration and one-sided RDMA — the extended latency ladder.
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the exam