Let's face it: VoIP isn't exactly new, but IP telephony's readiness for enterprise consumption is a fairly recent development. When it first appeared on the Internet scene, VoIP offered the ability for people to make free long-distance calls over the Internet. In fact, products like Internet Phone came with substantial buzz about how they let in-laws with Microsoft Windows have half-duplex speakerphone conversations through their PCs over the Net.
Lack of interoperability, poor quality of service, and a drop in traditional long-distance calling rates ultimately killed the first generation of consumer VoIP software. The short-lived voice-over-Internet craze of the late 1990s died. VoIP is still what historians might call a disruptive technologyit is changing the status quobut as it becomes more standardized, quality-driven, and accepted, it also becomes a more sustaining technology, just as the PSTN has been for decades. In this regard, VoIP has proven much more valuable in the enterprise than in the home.
This chapter helps you define the business case for VoIP. It guides you through readying your network, and your business, for next -generation telephony. This chapter is aimed at people who are justifying VoIP adoption with the promise of lowering operating costs and making system users more productive. It helps project managers decide between VoIP standards and vendors at the outset of the project. If you're a technical type, one who doesn't care necessarily about the financial impact of the technology, you'll learn what IP telephony's implications are for your network infrastructure.
Network convergence can mean more than just voice applications: many are using packet-based solutions for video conferencing, instant messaging, and security/surveillance. For the balance of this chapter, as we talk about preparing for the converged network, we'll zoom in specifically on voice.