Dimensioning of ACD - Systems


Automatic call distribution (ACD) forms the fundamental element of today's call centres. In accordance with flexible rules, an ACD system distributes a stream of incoming calls to agents who will provide a service or a product to the caller. If all agents are busy, the caller waits in a queue. Depending on the particular service the ACD system is designed for, a recorded announcement of constant length can be played before the incoming call is switched to an agent. Several different ACD applications are installed at customer sites: telebanking services, travel agencies, catalog orders on a service 800 base, hotline calls related to specific products and many more. The key issue in designing such systems is to determine the optimal operational point for a specific application. Most approaches focus on the traditional grade-of-service (GOS) aspect, where the ACD provider has to define his desired GOS parameters for the system (maximal loss, acceptable waiting times) and the ACD system will be dimensioned according to those restrictions. An ACD-specific aspect of the GOS approach is the so-called service-level objective x/y, which means that x percent of all handled calls are answered within y seconds.
In the project we deal with the problem of finding optimal parameters for ACD systems, in particular we will perform cost-optimal dimensioning for ACD systems with impatient customers and constant announcement time under arbitrary GOS constraints (loss, abandon probability as well as any waiting time characteristics). A very general ACD model is considered, based on a multi-server combined loss/waiting system with impatient customers allowing an announcement before entering the service. The accuracy of approximation techniques are compared with simulations. Within a flexible ACD cost model the modeling can be used to find cost optimal ACD system parameters under pre-defined service quality constraints. Realistic examples will be used to demonstrate the optimizing procedure.

Principal Investigators
Brandt, Andreas Prof. Dr. (Details) (Quantitative Business)

Duration of Project
Start date: 10/1993
End date: 06/1997

Publications
Brandt, A., Brandt, M., Spahl, D. and D. Weber. Modelling and optimization of call distribution systems. Proceedings of the 15th International Teletraffic Congress - ITC 15, Washington D.C., USA, June 1997, pp. 275-284.

Last updated on 2020-10-03 at 16:36