CCNP ONT Quick Reference Sheets: Exam 642-845

Chapter 2. Cisco VoIP

Introduction

Voice over IP (VoIP) is a set of technologies that seeks to replace traditional analog voice services. There are three main compelling benefits to VoIP:

• VoIP makes better use of network capacity. Traditional voice uses a 64-Kbps circuit, even when it is not active, but VoIP can use much less and no capacity when the line is not in use.

• VoIP allows new and revolutionary features, such as the following:

  • Integration of voice and data systems (so that operators get customer information popped on to the screen when a phone call arrives).

  • Voice CODECs can improve sound quality (at the expense of bandwidth).

  • Integration with new clients. Instead of an analog phone, VoIP clients can include television boxes, Personal Digital ...