Telephony: Voice Over IP

Overview

Voice over IP (VoIP) is a technology that enables voice traffic to be carried on data packet switched networks. In the past, there have been two types of networks used to move voice, video, and data communication. The first type of network was the Public Switched Telephone Network (PSTN). This was the system used by the local telephone company. This network was designed to carry only voice traffic. The second type of network was the data communications network found in many private company networks. This network carries data traffic. VoIP combines the two networks into one multiprotocol infrastructure. VoIP technology allows for central administration and management of both voice and data traffic. This provides a cost savings since only one organization is needed to meet both data and voice communication requirements.

Prerequisites

VoIP is an advanced topic. We recommend that you have experience configuring Cisco routers, or have completed the following courses:

Building Scalable Cisco Internetworks (BSCI)
Building Cisco Multi-layer Switched Networks (BCMSN)

Hardware/Software Requirements

The hands-on labs (Apply Your Knowledge Exercises) in this book can be covered in 2 different ways.

Two VoIP-capable routers (we used two Cisco 2600 series routers).

Two WAN Interface Cards (WICs) (we used two WIC 2T cards with high density connectors)

Two Voice Network Modules (VNMs)

Two FXS Voice Interface Cards (VICs) (we used the 2FXS VICs)

Back-to-back V.35 serial cable

The IOS on the routers must contain a “PLUS” feature set to support voice.

Delivery Method

Instructor-led, group-paced, classroom-delivery learning model with structured, hands-on activities

Performance-Based Objectives

Describe VoIP equipment and general telephony definition

Understand analog telephony, how the phone company operates and interacts with business, and how telephones work

Comprehend digital telephony and the conversion of analog to digital signals

Define the various Cisco products that offer VoIP features

Configure 2600 and 3600 series routers for VoIP

Design and implement VoIP into your network

Course duration

4 Days

Course outline

Lesson 1: Introduction to Voice over IP

Topic 1A: Sources of Information

Topic 1B: Cisco Voice Hardware

Topic 1C: Design

Lesson 2: Introduction to Analog Telephony

Topic 2A: Telephone Components

Topic 2B: Signaling

Topic 2C: Local Loop

Topic 2D: Voice Switches

Topic 2E: Trunk Types

Topic 2F: Trunk Line Seizure Signaling Types

Topic 2G: Echo and Echo Suppression

Topic 2H: Telephone Call Procedure

Lesson 3: Digital Voice Technology

Topic 3A: Digitizing Analog Signals

Topic 3B: Nyquist Theorem and Sampling

Topic 3C: Quantization

Topic 3D: Speech Coding Schemes

Topic 3E: Voice Compression

Topic 3F: Voice Packetization

Topic 3G: Telephone Voice Quality

Topic 3H: Channel Signal Types and Frame Formats

Topic 3I: Digital Channel Signal Types

Topic 3J: Signaling System 7

Lesson 4: OSI and TCP/IP

Topic 4A: OSI Reference Model Overview

Topic 4B: What is TCP/IP?

Topic 4C: TCP/IP Architecture

Topic 4D: TCP/IP: Addressing, Subnetting, and Routing

Topic 4E: Application and Internet Layer Protocols

Lesson 5: Real Time Transport Protocol

Topic 5A: RTP

Topic 5B: RTCP

Lesson 6: VoIP Network Architecture

Topic 6A: H.323 Architecture

Topic 6B: H.323 Signaling Overview

Topic 6C: Session Initiation Protocol

Topic 6D: Gateway Control Protocols

Lesson 7: Quality of Service

Topic 7A: Quality of Service Issues

Topic 7B: QoS Technology Solutions

Lesson 8: Cisco Voice Products

Topic 8A: Setting Up Your 2600 and 3600 Series Routers for Voice Over IP

Topic 8B: Setting Up Your AS5300 Access Server for Voice Over IP

Lesson 9: Configuring the Cisco 2600 and 3600 Series Routers for VoIP

Topic 9A: Voice Port Configuration

Topic 9B: Configuring POTS and VoIP Dial Peers

Lesson 10: Network Design and Architecture

Topic 10A: Six-step Design Process

Topic 10B: Current Network Audit

Topic 10C: Network Objectives

Topic 10D: Technologies and Services Review

Topic 10E: Technical Guidelines

Topic 10F: Capacity Planning

Topic 10G: Financial Analysis

Appendix A: H.323 Direct Endpoint Signaling