BY JOHN CLAYTON

Just as mainframes yielded to PC servers, proprietary PBXs will cede more and more of their territory to serverbased PBXs. Look for the first encroachments in small to midsized enterprises. Larger enterprises will soon follow, workgroup by workgroup, as the advantages of the serverbased PBX approach become more widely appreciated.

Although industry pioneers like PCBX made great strides building PCbased PBXs, the end result was little more than a DOS-based proprietary PBX. These early attempts were noble endeavors, but their potential was limited because of the lack of standards on which to build upon. Indeed, until recently, it was impossible to produce an open, server-based PBX. However, just two years ago, standards were agreed upon that allowed the creation of an open, server-based platform. These standards are, in effect, enabling the integration of PC and PBX systems.

The advantage gained through standards is an open and compatible telephony system that can be used by a wide variety of applications. And since one company cannot build all the applications you will need, the prevalence of industry-wide standards affords the user a high degree of flexibility in the development and acquisition of applications.

APIs
The most prevalent and wellknown standards enable CTI control between the PC clients and the server. In this arena, there are two established standards that are in competition for the world’s networks: Novell’s Telephony Server Application Interface (TSAPI) and Microsoft’s Telephony Application Programming Interface (TAPI). While acceptance by Novell and Microsoft has pushed telephony standards and servers so that networking is now ubiquitous, these standards are still being perfected. Novell’s TSAPI, the first open, implementable standard, first came on the scene in 1995. More recently, in July of 1997, Microsoft released its first client/server capable version in TAPI 2.1.

Voice Storage
Another area of standardization is in the storage of voice files. In this realm, it’s important for voice storage and messaging to comply with standard formats that are understood by Microsoft’s Windows. The commonality shared by these diverse technologies allows files and messages to be moved among servers and to other applications capable of understanding them.

S.100
A final, yet equally important standard, is one that enables the interconnection of multiple hardware pieces. This standard, previously known as the Dialogic SCSA Bus, is called the S.100 standard.

ENHANCED FUNCTIONALITY
Standards not only allow the creation of innovative technologies such as the server-based PBX, they ensure their usefulness and longevity. Because everything in a standardsbased environment can be added to or built upon, organizations can add additional functionality to these systems that extend their life cycles and combat obsolescence.

COST BENEFITS
The convergence of the server and the PBX produces myriad benefits, including significantly reduced costs of acquisition and operation. Organizations using PC-based server technology as the platform for telephony and voice are not locked into proprietary hardware, and can therefore leverage the cost advantages of server hardware. This provides benefits of scaleability as well. If additional capabilities, such as disk storage or more lines, are needed, an organization can add them incrementally, just as they would add more capability to their server for other reasons.

Further cost benefits are realized through the deployment of only one set of management tools and equipment. In terms of equipment, organizations no longer require two separate pieces of equipment to handle voice and data. This eliminates redundant hardware costs and is easier from a management perspective. By managing one server with telephony and business applications together, fewer IT professionals are needed to maintain, manage, and administer the combined telephony and data networking environment.

And there is the promise of saving money on long-distance phone calls. By moving voice across internal or corporate data networks, organizations can bypass toll charges for significant savings. Taking advantage of the emerging H.323 standard for voice over IP, bypassing toll charges can be achieved in the same way that PC client/server technology and architecture was deployed throughout corporations. While intricacies such as Quality of Service issues are still being worked out, proof of its arrival is substantiated by the many forwardthinking networking vendors and organizations that are planning their infrastructures accordingly.

TELEPHONY INTEGRATION: ADVANTAGES
Placing telephony functionality within an organization’s server provides both messaging and administration advantages. Having an organization’s voice and electronic messaging on the same server makes it is easier to bring them together in a unified messaging application — clearly the next step among many leading organizations. Standard user electronic messaging applications, such as OutLook, Exchange, GroupWise, and cc:Mail will seamlessly provide access to voice messaging.

Telephony functionality in the server means that it is connected to the network, enabling remote management and administration. This approach enables the network supervisor to administer telephony functions remotely, using PC Windows tools, saving thousands of dollars per year on moves, adds, and changes. Furthermore, the ability for the telephony system to access the same databases that your company uses for names and extensions also extends the ease of administration and integration.

Server-based telephony also allows seamless and complete integration with the industry standard client/server call control APIs: TSAPI and TAPI. This can be accomplished on the server without a separate CTI link or interface, eliminating bottlenecks and cost. Another integration benefit is the seamless integration with serverbased enhanced telephony applications such as IVR, fax-back, ACD, and intelligent call routing. Having the PBX switch functions integrated with the server eliminates the switch integration, bottleneck, and resource problems typically encountered when interfacing these server applications with traditional PBX systems.

SCALABILITY
Being server-based, organizations have a clear expansion path. As they grow, organizations can add boards incrementally to their servers to increase the system’s capacity. When a single server is outgrown, an organization can link servers together in a distributed fashion, preserving the existing PBX system. The emerging ability to transport calls across corporate IP networks will enable scaleability beyond single servers by distributing telephony functions seamlessly across multiple, distributed PBX servers.

THREE STEPS TO MARKET ACCEPTANCE
There are three important stages crucial to the success of the serverbased PBX. The first is an open, telephony server platform, at costs below those of traditional PBX solutions. The second important phase, is the availability of sophisticated, customizable IVR applications. This too is taking place, as vendors are joining hands, and bundling application development environment software with computer telephony software solutions. These product collaborations allow VARs and end-users to design computer telephony solutions to suit their specific business needs, which will lead to an array of vertical applications. The third, and ultimate, stage that will propel the server-based PBX to its greatest deployment will be the ability to send voice traffic across the corporate Intranet. The cost savings in this scenario will be impossible for businesses to neglect, and it is merely a matter of time before businessquality distributed telephony is deployable.

CONCLUSION
The compelling cost and functional benefits of server-based telephony and network telephony integration will quickly change the telephony landscape for the mid to small PBX market. By the year 2000, we can expect over half of all new telephony systems installed in mid to small enterprises to be serverbased. Penetration of the larger enterprise PBX market will quickly follow, as server-based telephony is deployed on a workgroup basis within larger organizations. This migration parallels the shift from mainframes to PC servers, and is a movement that many organizations are convinced will provide similar benefits.

John Clayton is the founder and CTO of NetPhone, Inc., which designs, manufactures and markets intelligent telephone systems (PBXs) and telephony applications for small- and midsized offices. NetPhone’s PBX servers are a new generation of telephone systems that integrate the power, ease-ofuse, and economics of PC servers with the familiarity and reliability of the telephone. These open, reliable telephone systems allow organizations to easily and affordably deploy a wide variety of computer telephony applications to increase sales, enhance customer service, reduce telephone costs, and boost staff productivity. For more informa tion, visit the company’s Web site at www.netphone.com.

A Paradigm Shift by Any Name

As with any technology that promises to redefine a particular market, attention is often focused on naming, or defining, that technology. And while most engineers will argue for one particular sobriquet over another, it is usually the folks in marketing who end up with the winning combination of words and acronyms.

Within the last year, there has been much discussion in the marketplace concerning technologies that effectively integrate an organization’s computer network and PBX system. While the nomenclature ranges anywhere from the “UnPBX” to “PC-Based PBX,” a more appropriate moniker for this technology might be “ServerBased PBX.” Designation notwithstanding, the server-based PBX is adding additional capabilities to the network server — allowing it to take control of telephony and voice messaging functions.