Speaking About VoIP
Pages: 1, 2

Stewart: Why is your book especially important now?

Kelly: VoIP is on the verge of taking off and becoming part of the public consciousness. Our current stage of development is analogous to where the Internet was in the late 1980s to early 1990s.

Jennings: VoIP is gaining support through its ability to provide viable services. In many cases, calling over the Internet from here to China offers a quality of service that rivals the PSTN. To the average end user, the difference in quality between a circuit switched call (PSTN) and a packet switched call (VoIP) is imperceptible.

Stewart: What is the single most important thing readers will be able to do after finishing your book that they couldn't do before?

Kelly: For many, mostly those who have no prior knowledge of VOCAL or, it will provide them with their first opportunity to download, test, and analyze the software. For those who have already worked with VOCAL, this book provides much greater detail about the data structures found within the code than any other material available on the Web site or elsewhere.

Jennings: Those advanced users will be able to gain a better understanding about the code and its functionality by referencing the book.

Stewart: Who is your intended audience?

Jennings: Essentially, those who have the wherewithal to download open source applications from the Internet and run them from a Linux server. These people may be hobbyists, students, or professional engineers, including those who make their living developing VoIP applications and solutions.

Dang: Although we attempt to expand our community by being inclusive, this is not beginner's software and it does require the user to have some sophistication with Linux to install and operate it.

Stewart: Tell us a little bit about the history of VoIP and how this book came to be.

Related Reading

Practical VoIP Using VOCAL
By David G. Kelly, Cullen Jennings, Luan Dang

Dang: Vovida Networks was founded in 1999 by Alan Knitowski and myself as an expression of our dissatisfaction with the status quo. Both of us came from a major telecom manufacturer that endeavored to maintain control over their customer's installations through building proprietary systems. Alan and I considered the Internet model of open standards and open source implementations as a better way to bring VoIP to the end users.

Kelly: During this time, Silicon Valley was booming and many talented engineers and business people were flocking to fledgling startups and the alternative culture being fostered therein. Vovida was a fun place to work and, like all small ventures, a place where each individual could see the impact of his or her work on the development effort. As we approached our first delivery milestones, Dang (Vovida's CTO) and Jennings (Vovida's VP of Engineering), while knowing nothing about writing books, agreed to terms with O'Reilly and soon found that their technical expertise in voice technology was not enough to bring this work to life. As any good executives would do, they delegated the responsibility of vitalizing this project to myself, Vovida's technical writer. I didn't know anything about VoIP, but managed to transform Luan's and Cullen's knowledge into something readable.

Jennings: While the material was being put together, the Silicon Valley economy turned from an all-time high to a devastating low and now appears to be bouncing back. At the same time, the Internet has shifted in the public's imagination from being a curiosity to a novelty to its present state of being a practical tool. VoIP is part of the practical tool-set for future Internet development and, from this point of view, the timing of the book's release could not be better.

Stewart: How important is VoIP? What is on the horizon for VoIP and VOCAL?

Jennings: VoIP will dramatically change the telephony landscape and voice will be treated like any other kind of data package. VoIP will be leading development of voice services into countries where installing traditional phone systems would be prohibitively expensive. VoIP is the wave of the future because of convergence, everything coming together, voice, video, and data (the source of the startup's name, Vovida), when applications in the same place, and the same time create a sum greater than its parts. For example, presence has helped instant messaging become much more useful that it would have been otherwise.

Dang: In the U.S., it took 80 years to create the PSTN and it is excellent. However, in China the requirement is to build the system in one-tenth the time, to serve ten times the number of customers at one-tenth the cost. That adds up to many constraints to meet at the same time, and we believe that VoIP is the only way to accomplish those goals.

Kelly: There is also the change towards flat-rate billing for long distance that can be traced to the emergence of VoIP. This has become most evident in the cellular phone packages being offered by service providers in the U.S. The cost of long distance has collapsed in the past ten years. The fact that you can make an excellent, free phone call over the Internet is a big reason why it will continue collapsing.

Stewart: Do you think the recent problems many of the large telcos are experiencing, like the bankruptcy of WorldCom, will have any effect on the acceptance of VoIP?

Dang: Our primary concern with the failure of these large companies, and the general slowdown in the service provider market, is that funding for new VoIP applications is becoming harder to find. In the long run, new companies will take the place of those that have failed, and what happened to WorldCom, Global Crossing, and others will be interesting history but not important to the day-to-day business of VoIP.

Kelly: We have noticed a sharp decline in the number of small companies at trade shows and the variety of open source projects available on the Internet. It seems that people are really concerned about keeping their jobs or finding jobs if they have been laid off. Soon, when companies start hiring more people and the fears of a downward-spiraling economy are abated, we believe that many developers will start where they left off and there will once again be a rich new world of ideas and products.

If you want to be a contrarian, you could say that this is an excellent time to start a small service provider organization and to slowly grow the business into sustainability. This type of venture would require a great deal of patience and may take a long time before it attracted substantial financial backing, but once the dust settles, there will be new opportunities for growth. Conrad Hilton started his hotel chain during the 1930s; who knows what exciting new markets may open up a few years from now.

Bruce Stewart is a freelance technology writer and editor.

O'Reilly & Associates recently released (July 2002) Practical VoIP Using VOCAL.