ACD-based Call Centers | Features/Function Enhancements

The fundamental function of a call center is to direct calls to a group of answering positions, equitably distribute the calls among the group members, and minimize the caller’s time in queue waiting for an agent. ACD is the general term used to describe this telephony function and was introduced as a PBX feature in the early 1980s. The early PBX-based ACD software options had limited flexibility in screening, routing, and queuing calls, and the MIS reporting function was minimal. ACD was developed as an enhanced version of the Uniform Call Distribution (UCD) feature, which itself was an enhanced version of Hunting.

ACD systems in the early 1980s were used only in very formal incoming call center environments, and annual shipments were limited to several hundred systems. In the early 1980s the only PBX system with an ACD capability that was competitive with stand-alone ACD systems was the Rockwell Wescom 580. Rockwell was also the leading manufacturer of stand-alone ACD systems at the time; its Galaxy ACD was the leading system in the market in terms of features and functions. The Rolm CBX had a basic ACD package, but most PBXs could offer little more than UCD for distributing calls. By the mid-1980s the market for ACD systems was growing almost 50 percent annually, and many PBX manufacturers looked at the call center application market for potential high profit margins. The first PBX manufacturer to offer a sophisticated ACD option that could compete with the Rockwell Galaxy ACD was AT&T. When AT&T introduced its latest version of System 85 in 1987, the ACD call screening, routing, and queuing functions were based on a new customer programming tool called Call Vectoring. Call Vectoring consisted of a series of programming commands that defined call coverage and treatment operations for each incoming call with flow charting methods. A new advanced MIS reporting system, based on an adjunct computer working behind the System 85, offered customers dozens of reports for call center management and monitoring. Supervisor positions, linked to the MIS reporting processing system consisted of GUI workstations displaying real-time call center information. The AT&T announcement marked a major change in the direction of PBX-based call centers.

After the AT&T announcement, other PBX manufacturers began development of similar ACD and MIS reporting options for their communications systems. By the mid-1990s the typical PBX/ACD offering was based on an adjunct application server required to run sophisticated call routing and treatment software, provide advanced MIS reports, and support supervisor PC client positions. Customers with complex call center application requirements would likely link the PBX/ACD system to a CTI application server to provide features such as screen pops, an coordinated voice/data screen transfer. An IVR would likely serve as a front-end system to screen calls and pass call-prompted data to the PBX/ACD program for analysis. New ACD features that improved call center efficiency and customer satisfaction levels included skills-based routing and agent skill profiling and mapping (Figure 2-4).

By 2000 PBX/ACDs dominated the call center market, accounting for more than 80 percent of total agent shipments. During the next few years the traditional voice-centric call center will migrate toward a mixed-media model that integrates the traditional ACD system with email distribution systems and Internet-based Web sites. The emerging IP-PBX system will be able to support the new-generation mixed-media agent position, which will handle incoming and outgoing voice calls, respond to e-mails, and chat with Web surfers on-line. Despite the changes in technology and the mix of voice calls, e-mail, and on-line chat, the fundamental functions of the new contact center system will be the same as those of the original ACD systems: equitable distribution of calls to agents and minimized response times for customer inquiries.