ABSTRACT
Planning departments for services such as support centers need to estimate the minimal level of resources needed to meet QoS requirements. We present a fast and numerically robust approximation to a typical QoS requirement, the wait time probability for an M/M/c queue. We then show its superiority to straightforward implementations, which have higher order of computational complexity and suffer from underflows and overflows. A possible extension of this model, once staffing levels have been determined, is to use a similar algorithm to size a VOIP network. We envision a method with similar numerical efficiency to the one reported here, except the queueing model needs to be GI/G/1 to evaluate the data network with VOIP in a DiffSrv Expedited Forwarding class.
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Index Terms
An efficient approximation to wait time in M/M/c queues with application to staffing planning
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