March 1999

Telephony + IP = More Connectivity, New Applications

BY TONY RYBCZYNSKI

The Web changes everything it touches - including voice communications. Granted, voice communications may not be the first thing people think of when they recount all the changes wrought by the Web. Furthermore, it must be said that voice communications has yet to feel the full force of IP convergence. Yet voice, while it is evidencing change more slowly, may, in the end, exhibit change that is all the more profound. And why should that be?

The spoken word, as a uniquely rich means of expressing human aspirations, seems to inspire uniquely rich mechanisms for amplifying and even realizing these aspirations. We've already seen just how sophisticated voice communications may become within a comparatively restrictive confine - the world of circuit-switching. It remains to be seen what voice will become in the comparative expansiveness of an IP-centric world.

THE PRECEDENT
In the beginning, Alexander Graham Bell established the feasibility of communicating at a distance (telecommunications) by transmitting voice signals over a wire. While telegraphs had been used for some time, the real significance in Bell's call to his assistant Watson is that his focus was on the primary way humans communicate, that is, on verbal communications.

The early patch-panel phone systems were quite human-friendly, with an operator providing the human touch. We then replaced the operator with electromechanical and then digital switching. Over the last hundred years, business phone systems, such as PBXs and key systems, have evolved dramatically, from basic voice switching systems to enterprise-wide multimedia communications systems, which typically provide a wide range of telephony services. These services include basic switch-level services, which could have been handled by the operator of old, as well as more sophisticated networking services, such as automatic least cost route selection and class of service routing, and advanced services and applications such as voice mail, mobility, and call centers.

All of these innovations have a common theme. They all point to how adding voice to a communications infrastructure can stimulate an efflorescence of functionality, how technology may bend to human needs, even those needs that were unidentified or didn't exist before the technology developed. In our endeavors to facilitate human communications over a distance in space, we begin with Bell's simple exclamation, straightforward cry, and we eventually arrive at CTI and call centers and video conferencing. (Moreover, these endeavors are complemented by our attempts to facilitate human communications over distance in time, which brings us to voice mail.)

We're now at the edge of a new wave of innovation. In the previous wave, innovation started when the telegraph met voice communications. In the new wave, IP networking is meeting voice communications. The interesting question, however, is how, in this new wave, we will enhance the ability of people to communicate and collaborate wherever they are and however they choose. For a hint at the answer to this question, let's look at the opportunities for enterprises. The most visible innovation in the enterprise space (and, perhaps, the most conspicuous example of what the new wave holds) is the IP (or soft) PBX.

THE IP PBX AND ITS BENEFITS
The IP PBX is a hardware/software solution that is, in essence, a LAN- or WAN-based PBX. Constituent or concomitant elements may include Ethernet networks, TCP/IP protocols, Windows NT servers, H.323 gateways (to connect to the PSTN), and call management software. While IP PBXs may vary in particulars, they all aim to treat the PBX as a kind of application, as opposed to a piece of proprietary iron.

The potential benefits of IP PBXs include:

• Easier moves and changes based on a single 10BaseT Ethernet connection to the desktop (the cost of wiring is not the issue since multiple copper pairs will still be delivered to each wall-plug).
• Reduced maintenance costs, compared to an average of $1/day/phone in today's systems.
• Increased openness being architected on open platforms (such as Windows NT), though the degree of openness when it comes to feature interoperability is still to be demonstrated.
• Lower cost WAN connectivity by consolidating voice over IP networks. (The consolidation is achieved by building V/IP gateways into every end device. This approach contrasts with existing systems that employ shared V/IP gateways.)
• Basic interworking with the installed base via gateways. (This approach contrasts with existing systems that require little additional functionality to achieve basic interworking.)
• New applications such as integrated messaging, tied to legacy voice mail, e-mail, and fax servers.

Of course, the above assumes that the LAN/WAN infrastructure has been upgraded to support voice transport; at a minimum, this implies LAN switching and some form of class of service support (for example, IEEE802.1p and DiffServ).

IP PBX CHALLENGES
The key challenges faced by IP PBXs as they evolve beyond the early adoptor stage fall into three categories:

1. Achieving very high availability expected of voice systems (adding multiple nines to existing LANs which have availability in the 99.5 percent range down, or, on average, are down for 7 minutes per day).
2. Providing a cost-effective range of end user appliance options, ranging from PC client software to USB-attached telsets to a range of single- and multi-line IP telephones. An added challenge is to minimize the (re-)training of the end user.
3. Providing meaningful feature interworking with the installed base.

This last challenge merits closer scrutiny, particularly since our aim is to leverage the connectivity of IP networks and the multimedia capabilities of IP for enriched person-to-person communications. As we will see, the interworking challenge has three main components: the need for more flexible access, the need for more flexible networking, and the need for consistent feature access across disparate environments.

Flexible Access
IP-based access to traditional voice services (over a LAN, over a private intranet, or over the public Internet) has significant value in supporting new business applications, large campus environments, telecommuters, and roadwarriors. IP-based access could be accomplished over a range of end user appliances, as indicated earlier. While the percentage of IP telephony subscribers is low, flexible access can be achieved by line-side V/IP gateways; as the penetration of IP subscribers increases, IP PBX implementations may prove economically attractive (subject to meeting the first two IP PBX challenges in the list just given).

Flexible Networking
IP-based trunking over a private intranet, or ultimately over the Internet, while preserving today's telephony networking features, can provide significant economic advantage. This also sets the stage for feature interworking between traditional voice and IP PBX environments.

The solutions will leverage the power of the PC running H.323-based collaborative applications with Web-based GUI's, multipoint control unit conferencing capabilities, and access to and interworking with Gatekeeper and the PBX desktop and mobility feature sets. Given that IP networks are less predictable than circuit-switched networks, the ability to monitor and adapt to dynamic network conditions is an important capability of V/IP gateways.

Feature Consistency
Value-added features and applications, such as unified messaging, are also relevant to the interworking challenge. Consider, for example, integrating voice, text and fax messaging applications to enable messaging system access and interconnection over IP networks. The Internet call center is another example, providing customer service centers with an enhanced level of transaction management capabilities. One IP PBX implementation architecture is based on evolving the call processing resident in voice networks to a client/call server model, shared by standard analog and digital phones and IP telephony devices. This approach would provide feature consistency across these environments.

TYPES OF PRODUCTS
So, given the challenges and opportunities peculiar to IP PBXs, what might we see in the way of products?

• IP telephony trunk-side gateways integrated in the PBX. These will provide the ability to monitor the data network and automatically re-route calls to traditional telephone networks if quality of service over the data network declines. Such gateways provide an integrated solution to standalone and router-based V/IP gateways available today.
• IP telephony line-side gateways integrated in the PBX. These will provide IP-based access to traditional voice services over a LAN, over a private intranet, or over the public Internet.
• Ethersets, IP appliances, and Universal Serial Bus (USB) telephones. USB telephones will be accompanied by advanced speech recognition applications using the power of a PC to offer users advanced call management and convenient access to CTI applications.
• Broadband PBX linecards. These cards, which will be deployable on a plug-and-play-basis, will support campus solutions such as 1-meg modems and long-distance Ethernet loop technology.
• Internet-enabled call center systems blending all kinds of traffic, including e-mail, circuit and packet voice traffic, and Web hits. These systems will include software that provides: 1) Routing, automated response templates, management and reporting for customer-generated e-mail; 2) Tracking of response times, agent efficiency, customer complaints, and the backlog of electronic inquiries; 3) Reporting of the number of e-mail requests generated from each page; 4) Web callback, faxback, and look-up features.
• Integrated platforms that combine key system and LAN/router functionality for small offices.

IP TELEPHONY IS NOT ABOUT FREE VOICE
The industry is currently focusing on integrating voice transport and data networks. But this is not the ultimate goal. The real objective is to combine telephony and IP to leverage connectivity and new applications, while providing business-critical availability, application-optimized performance, and lower cost of operations.

More broadly, leveraging the Internet and IP for enhanced telephony is less about doing traditional telephony in new ways, and more about enriching person-to-person real-time communications with multimedia capabilities built on IP. Ultimately, the objective is to make multimedia, person-to-person communications as reliable, simple, and secure as voice communications is today. It's also about enhancing customer service for WWW and e-commerce applications through voice communications by bridging the telephony and data worlds for competitive advantage. It's also about bringing down the barriers between telephony and access to information and transaction services.

Tony Rybczynski is director of strategic marketing and technologies for Nortel Networks' Enterprise Solutions. This business unit offers a full range of enterprise workgroup, campus, and wide-area unified networks, through direct and indirect channels. For more information, visit the company's Web site at < www.nortelnetworks.com. E-mail questions or comments to the author at tonyryb@nortelnetworks.com.