Estimate Number of Telephone Lines

Use the following applet to estimate telephony traffic items using an Erlang B algorithm.  It can also be used to determine how many checkout points are needed in a supermarket.

You can cut and past the data generated from the calculations.

Notes

Simply stated, the Erlang B algorithm calculates the percentage of calls blocked whereas the Erlang C algorithm calculates the percentage of calls that will be waiting to be answered and assumes there is a queue in which the calls are held before being answered.

Another way of stating this is that the Erlang B algorithm calculates the percentage number of callers who get a busy tone whilst the Erlang C algorithm calculates the percentage number of callers who have to wait to be answered.


Posted on 23 March 2000 by Graham Lawrence