Networking Topics
40 topics
- Networking
Clock Synchronization in Distributed Systems (NTP·PTP·TrueTime)
A technology that aligns the physical clocks of independently running nodes to a reference time or keeps the error within a known bound — comparing low-cost·wide-area NTP, PTP that reaches nanosecond level with hardware timestamps, and TrueTime that exposes error as an uncertainty interval and buys external consistency with commit-wait, with GNSS resilience and time security.
- Networking
Segment Routing (SR-MPLS · SRv6)
A source-routing architecture that carries the path in the packet as an ordered SID list to make the core stateless — SR-MPLS/SRv6 data planes, IGP integration, TI-LFA, network programming, and uSID.
- Networking
VPN (Virtual Private Network)
Building a virtual private network over a public network via encrypted tunnels — IPSec (site-to-site) vs. SSL (remote access) comparison, and the tunneling, encryption, authentication, and integrity technology elements.
- Networking
OPC UA (IEC 62541) for Industrial Data Interoperability
An essay-style guide to standardizing industrial communication and information models with OPC UA under IEC 62541. Covers address spaces, companion specifications, Client-Server and PubSub, security and certificate lifecycle, comparison with MQTT and Modbus, manufacturing and energy cases, and OT/IT interoperability.
- Networking
Intent-Based Networking (IBN) and Intent-Driven Network Operations
An essay-style treatment of network operations that express business goals, requirements, and constraints as machine-interpretable intent, realize them as policies and configurations, and continuously verify achievement through telemetry-based assurance—covering the reference architecture, model and lifecycle, comparison with SDN and script automation, a multi-branch payment-network case, 3GPP and TM Forum standardization, safe autonomy, and professional-consultant considerations.
- Networking
Network Slicing
Explains network slicing—creating multiple logically isolated end-to-end virtual networks penetrating the RAN, transport, and core on one physical infrastructure—covering its definition and background, SDN/NFV-based structure, per-domain partitioning techniques and isolation strength, the three-layer CSMF/NSMF/NSSMF management with S-NSSAI/NSSF, per-type design of eMBB/URLLC/mMTC and hard/soft isolation, and 3GPP standards trends with smart-factory and telemedicine cases, in an essay-style engineering exam format.
- Networking
Socket Communication
The two endpoints of communication identified by IP and port—covering TCP, UDP, and WebSocket types and a comparison with the HTTP communication method.
- Networking
TCP Congestion Control
TCP congestion control (CUBIC, BBR), which adjusts the congestion window (cwnd) in an AIMD sawtooth via slow start, congestion avoidance, fast retransmit and fast recovery, and detects congestion through loss and ECN.
- Networking
Web 3.0
The concept of Web 3.0, which returns ownership of data and assets to users through blockchain-based decentralization, its technical elements (smart contracts, tokens, DID) and applications, and its limitations such as scalability and regulation.
- Networking
High-Performance, Low-Latency Wireless LAN Design Based on Wi-Fi 7 (IEEE 802.11be)
A professional-engineer essay-style overview of Wi-Fi 7 based on IEEE 802.11be-2024 — the principles of 320 MHz channels, MLO, 4096-QAM, OFDMA, and Multi-RU, a comparison with Wi-Fi 6, 5G, and wired networks, and RF, backhaul, security, observability, and phased-adoption strategy.
- Networking
MPLS (Multi-Protocol Label Switching)
An L2.5 connection-oriented technology that attaches a 20-bit label to IP packets to traverse the core via exact-match switching — LER/LSP, FEC, label stacks, LDP/RSVP-TE/MP-BGP distribution, L3/L2 VPN, traffic engineering, FRR, and the evolution toward segment routing (SR-MPLS, SRv6).
- Networking
NFC (Near Field Communication)
Contactless short-range communication at 13.56 MHz within 10 cm—covering reader, P2P, and card-emulation modes and applications in mobile payment and tagging.
- Networking
Open RAN (Open Radio Access Network) Architecture and RIC-Based Intelligence
An overview of the structure, interfaces, deployment, performance, security, and multi-vendor operation strategy of Open RAN, which combines RU/DU/CU functional split, open interfaces, virtualization, and intelligent control based on SMO, Non-RT RIC, and Near-RT RIC.
- Networking
Network Functions Virtualization (NFV)
A network cloudification technology that decouples network functions locked into dedicated hardware into software (VNFs) on general-purpose servers and automates the lifecycle with ETSI MANO (NFVO, VNFM, VIM) — evolving toward CNF, 5G, and edge.
- Networking
QoS: DiffServ and IntServ
Architectures that guarantee network service quality. Comparing IntServ (per-flow RSVP reservation, hard guarantee, low scalability) with DiffServ (DSCP/PHB class differentiation, stateless, high scalability), with WFQ/WRED queuing linkage and SDN and 5G slicing trends.
- Networking
Time-Sensitive Networking (TSN)
A set of deterministic Ethernet technologies that adds time synchronization (802.1AS), time-aware scheduling (802.1Qbv), lossless redundancy (802.1CB), and central configuration (802.1Qcc) on top of standard Ethernet to guarantee bounded latency and low jitter, covering the real-time communication foundation of IT/OT convergence, autonomous driving, and smart factories.
- Networking
Network Subnetting and Supernetting
Concepts of subnetting and supernetting, with a worked calculation of the mask (255.255.255.192) and assignable IPs (62) when dividing 192.168.100.0/24 into four subnets.
- Networking
Software-Defined Networking (SDN)
The three-tier architecture and control-plane characteristics of SDN, which separates the control plane from the data plane so that a central controller exercises global control, the OpenFlow operating procedure, and the evolution toward NFV and intent-based networking.
- Networking
Information Theory and Shannon's Theorems
Quantifying information as entropy. The first theorem (compression limit = entropy), the second theorem (zero error within capacity), and Shannon-Hartley (C = B*log2(1+S/N)), extended to AI.
- Networking
Rate Limiting and Traffic-Control Algorithms
A traffic-control technique that caps the number of requests within a time window — covering token bucket, leaky bucket, and fixed/sliding window algorithms, gateway- and Redis-based distributed implementations, and use of 429 and Retry-After responses to secure availability, fairness, cost, and security.
- Networking
WFQ (Weighted Fair Queuing)
A queuing scheme that approximates GPS per packet (PGPS), assigns weights to traffic flows, and allocates bandwidth byte-fairly in order of virtual finish time. It solves FIFO monopoly, PQ starvation, and WRR size-unfairness, with CBWFQ, LLQ, and DRR extensions.
- Networking
DNS (Domain Name System) and DNS Security
A hierarchical, distributed name-resolution system that translates domain names into IP addresses — covering recursive/iterative queries and caching principles, record types, threats such as cache poisoning and amplification DDoS, and mitigations including DNSSEC (integrity) and DoH/DoT (confidentiality).
- Networking
MQTT (Message Queuing Telemetry Transport)
A publish/subscribe-based lightweight IoT messaging protocol — an in-depth note covering brokers, topics, QoS 0/1/2, LWT, Retain, and Keep Alive, through to MQTT 5.0 (shared subscriptions, User Property).
- Networking
SDR (Software Defined Radio)
Implementing radio signal processing (modulation/demodulation, filtering, protocols) in software so one device supports multiple standards and frequencies. Early digitization and software processing provide flexibility and scalability, forming the basis for 5G/6G software-defined infrastructure such as cognitive radio, Open RAN, and satellite (NTN).
- Networking
6G Mobile Communication
The goals, core technologies, comparison with 5G, and standardization trends of 6G based on ITU-R IMT-2030 (Tbps, 0.1 ms, terrestrial-satellite integrated NTN, AI-native, integrated sensing and communication ISAC).
- Networking
Load Balancing and L4/L7 Traffic Distribution
A technique that distributes requests across multiple servers to secure availability, scalability, and performance — this essay covers the difference between high-speed IP/port-based L4 and fine-grained content-based L7, distribution algorithms, health checks, session externalization, GSLB, and redundancy, and its evolution toward the cloud and the service mesh.
- Networking
VXLAN (Virtual eXtensible LAN)
A MAC-in-UDP tunneling technology that creates a 24-bit VNI-based L2 overlay over L3 to overcome the limitations of VLAN.
- Networking
SATIN (Satellite-Aerial-Terrestrial Integrated Network)
SATIN, a 6G-oriented three-dimensional wireless network that integrates satellite (wide-area), aerial (drones, HAPS), and terrestrial (high-capacity) layers into a single control plane: roles by layer, handover, integration technologies, applications in disaster response, UAVs, and remote areas, and spectrum and security challenges.
- Networking
SD-WAN (Software-Defined WAN)
A WAN architecture that applies SDN's plane-separation principle to the wide-area network, binding Internet, LTE, and MPLS circuits with an encrypted overlay and centrally controlling paths in software according to application-aware policies and real-time link quality.
- Networking
BGP (Border Gateway Protocol)
The backbone Internet protocol that exchanges policy-based reachability between ASes using AS_PATH and path attributes (LOCAL_PREF, MED, Community) — eBGP/iBGP, best-path selection, a comparison with IGPs, and RPKI-based security.
- Networking
IPv6 and IPv4-to-IPv6 Transition Technologies
This essay covers IPv6, the next-generation Internet protocol that resolves IPv4 exhaustion and the limits of scalability and security through 128-bit addressing, a fixed header, SLAAC/NDP, and integrated IPsec, and addresses IPv4-to-IPv6 transition technologies such as dual stack, tunneling, and NAT64 along with IPv6-specific security threats such as RA spoofing and their countermeasures from an in-depth perspective.
- Networking
Non-Orthogonal Multiple Access (NOMA)
The principles of NOMA, which superimposes and shares the same time and frequency by power difference and separates signals with SIC, its core technologies (power allocation, superposition coding, SIC), a comparison with OMA, and application to 5G/6G hyper-connectivity.
- Networking
WebRTC (Web Real-Time Communication)
An open technology that transmits audio, video, and data peer-to-peer with ultra-low latency using only standard browser APIs (getUserMedia, RTCPeerConnection, RTCDataChannel) without plugins—covering SDP offer/answer signaling, ICE (STUN/TURN)-based NAT traversal, mandatory SRTP/DTLS encryption, the Mesh/SFU/MCU scaling structures, trade-offs against HLS/WebSocket, and infrastructure-sizing and security considerations.
- Networking
Content Delivery Network (CDN)
Infrastructure that replicates content across geographically distributed edge-server caches and directs users to the optimal edge to reduce latency and distribute origin load—covering pull/push caching and invalidation strategies, DDoS and WAF security, and its evolution into a distributed delivery platform via edge computing.
- Networking
QUIC and HTTP/3
QUIC, which integrates TLS 1.3, stream multiplexing, and reliability over UDP to eliminate transport-layer head-of-line blocking and enable 0-RTT connections and connection migration, and HTTP/3, the next-generation web protocol built on it.
- Networking
SASE (Secure Access Service Edge)
An architecture that converges SD-WAN (connectivity) with SWG, CASB, ZTNA, and FWaaS (security = SSE) at the cloud edge in an identity-centric, single-pass model—delivering performance by eliminating backhaul and securing perimeterless environments through zero trust.
- Networking
Considerations for Building a Private 5G Network
Delivering ultra-low latency and high reliability with dedicated 5G — ensuring stability through redundancy, MEC, and slicing, and avoiding interference through frequency planning, beamforming, and interference coordination.
- Networking
SCTP (Stream Control Transmission Protocol)
An overview and the characteristics of a transport protocol offering reliability, message orientation, multi-streaming, and multi-homing, plus its 4-way (cookie) handshake structure and operation.
- Networking
TCP 3-way / 4-way Handshake
The TCP connection and teardown procedures that establish a connection via the 3-way SYN → SYN+ACK → ACK and release it via the 4-way FIN → ACK → FIN → ACK.
- Networking
RIP vs. OSPF (Routing Protocols)
A comparison of the distance-vector (RIP) and link-state (OSPF) routing protocols in terms of algorithm, metric, convergence speed, and scalability.