VoIP Course

Lesson 1 • VoIP System Architecture Overview

Maps the major components—endpoints, gateways, and call servers—and their relationships. Builds the mental model students use throughout the course.

Lesson 2 • Digitising and Packetising Voice

Explains how analogue voice is sampled, encoded, and segmented into IP packets. Connects audio physics to network transmission concepts.

Lesson 3 • VoIP Standards and Protocols Landscape

Surveys the major protocol families governing signalling and media in VoIP. Sets the stage for deep dives in later chapters.

Lesson 1 • Network Address Translation and VoIP

Examines how NAT disrupts VoIP signalling and media paths and the solutions that restore connectivity. Prepares students for real-world deployment challenges.

Lesson 2 • Quality of Service Principles

Introduces QoS mechanisms that prioritise voice traffic over data. Students learn to identify and apply the correct QoS model for a given network.

Lesson 3 • IP Addressing and Subnetting

Covers IPv4 and IPv6 addressing, subnet masks, and CIDR notation as applied to VoIP device provisioning. Ensures students can assign and plan address spaces.

Lesson 4 • Routing and Switching Fundamentals

Explains how packets traverse routers and switches from endpoint to endpoint. Directly supports understanding of call path and latency sources.

Lesson 1 • SIP Call Flow Scenarios

Walks through basic and advanced call flows including registration, basic call, hold, and transfer. Bridges protocol theory to observable network behaviour.

Lesson 2 • SIP Messages and Transaction Model

Analyses request methods, response codes, and the transaction state machine. Students gain the ability to interpret raw SIP message exchanges.

Lesson 3 • SIP Architecture and Components

Defines User Agents, Proxy Servers, Registrars, and Redirect Servers and their interactions. Establishes the vocabulary used in all subsequent SIP sections.

Lesson 4 • SDP and Media Negotiation

Explains how Session Description Protocol within SIP negotiates codec, port, and media type. Connects signalling to the media plane established afterwards.

Lesson 1 • Real-Time Transport Protocol

Details RTP packet structure, sequencing, and timestamping for synchronised media delivery. Students learn to analyse RTP streams in capture tools.

Lesson 2 • DTMF Transmission over VoIP

Covers in-band, RFC 2833, and SIP INFO methods for transmitting touch-tone signals. Ensures students can configure reliable DTMF for IVR and dial-plan integration.

Lesson 3 • RTCP and Stream Monitoring

Covers RTP Control Protocol reports for measuring packet loss, jitter, and round-trip time. Enables students to monitor live call quality using RTCP data.

Lesson 4 • Voice Codec Fundamentals

Explains waveform and parametric coding approaches and their quality-bandwidth trade-offs. Provides the basis for codec selection decisions in deployment.

Lesson 1 • IP PBX Architecture and Components

Describes the functional blocks of an IP PBX: core engine, database, and media server. Establishes the deployment model used in subsequent configuration sections.

Lesson 2 • Auto-Attendant and IVR Configuration

Guides students through building menu-driven auto-attendants and interactive voice response flows. Applies dial plan and media concepts to a common enterprise feature.

Lesson 3 • Dial Plan Design and Configuration

Teaches pattern matching, routing logic, and context-based call routing within a PBX dial plan. Students build a complete dial plan from requirements.

Lesson 4 • SIP Trunking Configuration

Covers provisioning SIP trunks to carriers for PSTN access, including authentication and codec negotiation. Connects the internal PBX to external telephone networks.

Lesson 1 • SIP Authentication and Access Control

Covers SIP digest authentication, IP allowlisting, and rate limiting to prevent unauthorised access. Students configure these controls on a live PBX.

Lesson 2 • Encrypting Signalling with TLS

Explains Transport Layer Security applied to SIP to prevent signalling interception and tampering. Covers certificate management for VoIP endpoints.

Lesson 3 • Intrusion Detection and Fraud Monitoring

Introduces tools and techniques for detecting anomalous call patterns and active attacks in real time. Prepares students to respond to security incidents.

Lesson 4 • Encrypting Media with SRTP

Details Secure Real-Time Transport Protocol key exchange and encryption of voice media streams. Ensures students can enable end-to-end media confidentiality.

Lesson 1 • Packet Capture and SIP Trace Analysis

Teaches capturing and filtering VoIP traffic with protocol analysers to reconstruct call flows. Students practise reading SIP ladders and RTP statistics.

Lesson 2 • Call Quality Metrics and Measurement

Defines MOS, R-factor, latency, jitter, and packet loss thresholds for acceptable voice quality. Gives students objective benchmarks for quality assessment.

Lesson 3 • PBX Log Analysis and Debugging

Guides students through reading PBX verbose logs to trace call setup failures and feature errors. Builds systematic log-reading habits for faster resolution.

Lesson 4 • Network-Layer Troubleshooting

Applies ping, traceroute, and path MTU discovery to isolate network-layer causes of call failure. Connects network symptoms to VoIP-specific effects.

Lesson 1 • VoIP in Cloud and Virtualised Environments

Addresses deploying PBX and media servers on virtual machines and cloud platforms with voice-grade performance. Covers hypervisor tuning and cloud network constraints.

Lesson 2 • Session Border Controllers in Depth

Examines SBC functions: topology hiding, transcoding, admission control, and security enforcement. Positions the SBC as the enterprise-to-carrier demarcation point.

Lesson 3 • High Availability and Redundancy Design

Covers active-passive and active-active PBX clustering, database replication, and failover triggers. Students design an HA topology meeting defined recovery objectives.

Lesson 4 • Capacity Planning and Performance Tuning

Applies traffic engineering models to forecast call volume and size infrastructure accordingly. Students tune OS and application parameters for maximum throughput.