Networks & The Internet
The global infrastructure behind digital communication: fiber-optic cables, BGP routing, DNS, TLS, Wi-Fi, and cellular radio.
How the Internet Actually Works
Submarine fiber cables, autonomous systems, BGP path routing, and the physics of packet switching
Inquiry Learning Paths
Structured sequences designed to take you from a familiar question to complete first-principles understanding.
How the Internet Carries Information Around the World
Follow a network request across every physical and protocol layer: BGP autonomous systems, IP packet hops, submarine optical amplifiers, 802.11 Wi-Fi radio modulation, Anycast DNS, and TLS cryptography.
“When you tap a link or type a web address on your phone, how do your request packets travel through air as radio waves and across ocean floors as laser pulses to fetch a webpage in milliseconds?”
How the Internet Actually Works
Introduces the global network of networks: 115,000+ independent Autonomous Systems exchanging reachability paths via BGP-4 and forwarding 1,500-byte packets without central control.
How Packets Actually Travel Across the Internet
Follows an individual packet hop-by-hop: TCP segmentation, IPv4/IPv6 TTL decrementing, longest-prefix-match TCAM lookups, and dynamic rerouting around severed links.
How Fiber-Optic Cables Carry Light Across Oceans
Descends to the ocean floor where 99% of intercontinental traffic travels as 1550 nm infrared laser light through silica fibers amplified every 70 km by erbium-doped optical repeaters (EDFAs).
How Wi-Fi Actually Works
Explains the wireless last hop: how your router maps digital bits onto 2.4/5/6 GHz QAM radio subcarriers (OFDMA) and coordinates airtime via CSMA/CA collision avoidance.
How Cellular Networks Route Calls and Data
Extends wireless routing to mobile wide-area telecommunications: microsecond base station MAC scheduling, RRC connection handshakes, seamless inter-tower handovers, and GTP tunnels across LTE and 5G cores.
What Happens When You Type a Website Address
Connects packet transport to the application layer: hierarchical Anycast DNS resolution, the TCP three-way handshake, TLS 1.3 key exchange, and browser DOM rendering.
How Public-Key Cryptography Actually Works
Explains the mathematical miracle behind HTTPS and TLS: how two computers that have never met establish an encrypted channel over public fiber using Diffie-Hellman and elliptic-curve cryptography.
All Published Explainers
Every verified first-principles analysis in this domain.
How the Internet Actually Works
Submarine fiber cables, autonomous systems, BGP path routing, and the physics of packet switching
How Wi-Fi Actually Works
Electromagnetic radio waves, 2.4/5/6 GHz channels, CSMA/CA collision avoidance, and orthogonal frequency division multiplexing
How GPS Actually Knows Where You Are
Orbital atomic clocks, pseudorange trilateration, relativistic time dilation, and the four-satellite geometry equation
What Happens When You Type a Website Address
URL parsing, recursive Anycast DNS, ARP, the TCP 3-way handshake, TLS 1.3 key exchange, and browser DOM rendering
Why Wi-Fi Gets Worse Through Walls
Dielectric attenuation, skin depth, Fresnel zone obstruction, and dynamic modulation fallback
Why GPS Sometimes Shows the Wrong Location
Ionospheric plasma delay, urban canyon multipath reflections, Dilution of Precision, and Assisted GPS
How Packets Actually Travel Across the Internet
From MTU slicing and IP headers to BGP router forwarding, submarine fiber lasers, and TCP reassembly
How Cellular Networks Route Calls and Data
Base station radio schedulers, RRC connection handshakes, inter-cell handovers, GTP tunnels, and VoLTE/5G core architectures
How Fiber-Optic Cables Carry Light Across Oceans
From Snell's law and total internal reflection to 1550 nm silica windows, Erbium-doped optical amplifiers, and 10,000-volt seabed repeaters
How Bluetooth Pairs, Frequency Hops, and Transmits Data
From 2.4 GHz ISM interference and adaptive frequency hopping (AFH) to piconet clock synchronization, ECDH pairing, and Bluetooth Low Energy (BLE)
How Satellite Navigation Constellations Operate
From Keplerian orbital mechanics and Walker Delta constellations to space-hardened atomic clocks, L-band CDMA modulation, and multi-GNSS interoperability
How the Domain Name System (DNS) Resolves Names Across the Planet
From ARPANET's centralized HOSTS.TXT bottleneck to 13 anycast root server clusters, iterative referral chains, authoritative zone files, and DNSSEC cryptographic trust
How 5G Beamforming and Massive MIMO Transmit Gigabits
From 64T64R active antenna systems and phased-array constructive interference to channel state information (CSI), spatial multiplexing, and millimeter-wave physics
How Fiber-Optic Cables Transmit Light Across Oceans Without Signal Loss
From Snell's total internal reflection and ultrapure silica synthesis to erbium-doped fiber amplifiers (EDFAs), chromatic dispersion management, and dense wavelength division multiplexing
Technical Systems & Protocols Analyzed
Hardware, protocol switches, and central clearing houses examined in this hub.