It is important to understand the terminology and concepts when dealing with a new technology. This chapter introduced and explained key VoIP components. Understanding VoIP requires knowledge of both data networking and telephony. The main PSTN components were introduced: voice encoding, switches, PBXs, signaling, and telephones. Likewise, the main VoIP components were introduced: codecs, protocols, telephony servers, IP PBXs, gateways, and IP phones.
Now that you are familiar with the basics of VoIP and its resemblances toand distinctions fromthe telephone network that you are accustomed to using, the next chapter covers the potential benefits of VoIP, and tries to separate some of the pie-in-the-sky VoIP fantasies from the real returns you can expect from your own implementation.