Using this calculator, you can determine the required number of telephone lines depending upon the expected Busy Hour Traffic of the telephone network.
Estimating the number of lines – Erlang B Calculator
This calculator, based on Erlang B load estimation model, lets you estimate the number of telephone lines required for your call-center depending upon the expected number of calls.
Load estimation model
The Erlang B load estimation model is an analytical model developed by the Danish scientist A.K. Erlang and is designed to calculate the blocking of calls. The model is used to design telephone systems for estimating the number of telephone lines necessary for communication with PSTN.
For estimating the number of lines, you must evaluate two parameters of the telephone network during Busy Traffic Hour
Frequency of calls (number of calls per hour), and