are a variety of network services (outside lines and their capabilities) that can be used to expedite Call Cen- ter ACD function. 88 & The Telecom Handbook CHAPTER 4 Any type of outside line that works in a PBX can work in an ACD including T1/PRI, combination trunks and DID trunks. The number and type of outside lines to order is an important part of the overall system design and depends upon call vol- ume, service level objectives and number of customer service representatives. Traffic engineering tables for Call Center ACDs use dif- ferent parameters than for PBXs to how many outside lines are needed. Network based services often used in call centers to route the calls include DNIS and ANI. DNIS (Dialed Number Identification Service): Many sepa- rate 800-type toll-free telephone numbers may share an "800" trunk group. DNIS allows the receiving Call Center equip- ment to recognize the digits the caller dialed, and base inbound call routing accordingly. The digits dialed may be translated to a "reason called" and displayed for the agent, prompting an appropriate greeting. ANI (Automatic Number Identification): In some locations, the telephone number from which the incoming call is placed can be recognized by the Call Center equipment. This can then be used for inbound call routing or for an automated database access. A similar function to ANI known as Caller ID, also delivers the calling telephone number. Other Call Center Capabilities Predictive Dialing Many Call Centers are designed to both take incoming calls and place outgoing calls. The same group of agents may be re- sponsible for both sales and collections. The sales calls are primarily incoming, and the collections calls are placed during lulls in incoming traffic. The Telecom Handbook * 89 THE ACD Outbound calls may be placed automatically using predic- tive dialers. Predictive dialers analyze incoming call traffic and agent activity, then automatically place outgoing calls when agents are about to be available. These predictive dialers help manage- ment