Earlier in this chapter, CTI was described from the perspective of a PBX environment, because the technology originated in the PBX community. In a call center application, the PBX switch is capable of relaying information that the PC can interpret and that operators can use to respond to a caller rapidly. CTI is the technology that enables a range of multifaceted call management features to be implemented in a call center. Advances in telephone and computer technology, as well as in other technologies, such as data warehousing and database management systems, have resulted in the increasing sophistication of modern call centers.
As described previously, CTI is made possible by the integration of many different components, subsystems, applications, and technologies and is based on an "open system" concept. Open systems and common standards allow a telephony server to be added to an existing LAN, thereby making possible the sharing of applications across an enterprise. In this environment, legacy systems also play a major role by providing customer data and employing other long-standing internal corporate standards. CTI applications can share LANs with different servers because telephony APIs have been developed by leading network specialists and customer premise equipment (CPE) manufacturers. Although CTI came from "closed proprietary" roots, its evolution has motivated the telecommunications community to adopt an open system/multivendor environment, a process referred to previously in this chapter.
The integration of computing and telephony, with its myriad of components and standards, is a natural environment for this approach in which numerous players can contribute knowledge and expertise at the right point in the process. On the computer side of the CTI house, major computer vendors are active in client/server architecture and CTI solutions. At the same time, switch vendors have endorsed two of the more prevalent APIs—TSAPI and TAPI (see the Glossary in Appendix B). The significant advantage of open system architectures is that they provide developers the opportunity to focus on designing the application, rather than getting involved in the various components or peripherals it may try to control. Application development in CTI is facilitated using APIs provided by operating system designers and manufacturers of peripheral equipment, while CTI developers are free to concentrate on their own application requirements.
Previous descriptions of CTI in this chapter have stressed the high level of automation this hybrid technology brings to call center operations. To accomplish the goals of an organization planning to implement a fully automated call center, the following must be considered and evaluated:
Integrating the new CTI architecture with currently installed systems and incorporating the capability for future growth
Minimizing requirements for new hardware and software on existing PCs and in the PBX
Incorporating industry-standard hardware and software
Building in the capability to track and report on call center operations, including operator productivity and the effectiveness of the CTI implementation
An effective call center operation will keep pace with the communications preferences of customers, while maximizing network resources and customer service, by integrating a wide range of communication tools with the organization's human resources and databases.
Early CTI implementations that used switch links had a number of designations for the link or interface between the computer and the PBX, but what they had in common was architecture rooted in computer-to-mainframe PBX. This complex, high-end system was the result of technology alliances between big switch manufacturers and big computer manufacturers, which yielded an enterprisewide solution. In a typical large call center operation, the application ran on a minicomputer/mainframe and controlled a PBX using an intelligent link. The user's screen was controlled by the same application so that the application could coordinate the call arriving at the desk with the proper and timely presentation of information. If the operator needed to transfer the call to a supervisor, the application made sure the information screen traveled with the call.
The new approach uses a telecom server, which is installed as another node on a workgroup LAN and equipped with the hardware and software elements necessary to deliver CTI solutions to that workgroup. The telecom server connects directly to the public network to handle all calls coming into the group and connects directly to the desktop client to deliver those calls. This approach allows all the "priority" customer contacts to bypass the enterprise PBX. As a result, the enterprise PBX no longer needs to be upgraded. The telecom server has a few simple connections back to the legacy PBX to allow internal calls between the workgroup and the rest of the organization, a feature that is one of the major technological advances in a CTI implementation.
Telecom servers contain a basic computing component, which is enhanced for CTI applications by adding four card types:
A digital trunk card to connect to advanced network services
A digital line card to transfer voice or video connections to the desktop
An analog trunk card to connect internal voice calls to the legacy PBX
A special-purpose resource card with a range of available technologies configured to match the services required
The traditional PC bus is not designed to handle the large bandwidth required to transport real-time voice and video information, for example, from the digital trunk card across the digital line card or to the voice processing card. To solve this problem, a secondary telecom bus is added to the server architecture.
Telecom servers extend the range of services available to the CTI application developer. Basic call control can now be integrated with DSP (digital signal processor) cards to deliver the broad range of services described next.
Voice response systems were discussed briefly as one of the call-handling features enabled by CTI. This feature involves a single-card voice mail system that is designed by programming a DSP resource card to compress the caller's voice so that it can be stored on a mass storage device such as a hard disk. The voice is already in digital format when it arrives from the digital trunk or digital line card. The application software in a voice mail server is basically a simple file-and-retrieval system available from several vendors that uses a desktop PC application to control the system.
IVR systems use essentially the same technology as voice mail and can be designed with a single DSP card. IVR applications allow users to create structured scripts that guide the caller through a series of menu options to obtain a final response. The IVR will play digitally stored messages and solicit a response from the caller at each step, generally using a Touch-Tone telephone pad. The response will then cause the next set of messages to be played, according to the script.
Speech recognition is another DSP-based technology that can be delivered to the server as a resource card. It gives the computer the capability to analyze digitized voice signals, compare them with other voice patterns, and recognize the words being spoken. This technology can be used to supplement IVR systems in situations where the user can't use the Touch-Tone keypad or to reduce the number of menus that the caller has to navigate.
Text-to-speech or speech synthesis technologies are another resource card option, enabling the computer to produce speech from written or spoken information. This capability is useful for e-mail or free-form messages when a terminal is unavailable (e.g., at the airport, on a cellular phone, etc.)
The DSP card can be programmed to function as a fax modem, which provides a shared fax server resource. The fax image can be downloaded over the LAN and converted by the fax card, then transmitted over the digital trunk to the network. In reverse fashion, an incoming fax from the network will be converted to file format and sent to the desktop PC.
Media conversion, along with other technologies, has the potential to improve access to information from anywhere, a useful feature for mobile workforces.
OCR is another DSP-based technology that converts a scanned image into text. When used with fax images, it can convert an incoming fax to a document that can be edited or pass it to a text-to-speech application to be read aloud.