Instructions for Erlang B Spreadsheets K Fletcher 1994

document.xls Page 1 of 1 Printed 04/19/2023 19:17:44

Instructions for useThis calculator shows how the ErlangB graphs can be drawn using an Excel Spreadsheet

It allows up t 140 ServersThe table and graph are for 20 columns (values of offered load)and 18 rows in the multi table

The sheet, "ErlangB Calcs", is in several parts1 The part which actually does the ErlangB calculations (RED AREA)

This part goes out for at about 150 columns to the rightSet colour to white if you want to print this area

2 The single value calculator (GREEN AREA)This is a box near the upper left corner which allows you to insert a value for

A Erlangs of offered traffic, andM Number of Servers

These fields are edited as follows:A Edited for negativeM Edited for negative, and for integer value, and for not to exceed the max value

The resulting probablity of congestion (GOS) figure is presented in the next cell belowSet colour to white if you want to print this area

3 The multiple values calculator (BLUE AREA) - This is the area which creates data for the Graph

Change the start and increment values for A in the row above the table properChange the start and increment values for M (to the left of table)YOU MUST HIT THE 'CALC TABLE' BUTTON located intop left corner of the table!

4 The graphThis will plot automatically

HAVE FUN, and ENJOY LIFE!KenF

Erlang B Calculations and Graph - Large Size K Fletcher 1994

document.xls Page 2 of 1 Printed 04/19/2023 19:17:44

A Erlangs of Offered TrafficM 0.09% 0.010 1.000 2.000 3.000 4.000 5.000 6.000 7.000 8.000 9.000 10.000 11.000 12.000 13.000 14.000 15.000 16.000 17.000 18.000 19.000 Servers

1 0.99010% 50.00% 66.67% 75.00% 80.00% 83.33% 85.71% 87.50% 88.89% 90.00% 90.91% 91.67% 92.31% 92.86% 93.33% 93.75% 94.12% 94.44% 94.74% 95.00% 1S 2 0.00495% 20.00% 40.00% 52.94% 61.54% 67.57% 72.00% 75.38% 78.05% 80.20% 81.97% 83.45% 84.71% 85.79% 86.73% 87.55% 88.28% 88.92% 89.50% 90.02% 2e 3 0.00002% 6.25% 21.05% 34.62% 45.07% 52.97% 59.02% 63.75% 67.55% 70.64% 73.21% 75.37% 77.21% 78.80% 80.19% 81.40% 82.48% 83.44% 84.30% 85.08% 3r 4 0.00000% 1.54% 9.52% 20.61% 31.07% 39.83% 46.96% 52.73% 57.46% 61.38% 64.67% 67.45% 69.85% 71.92% 73.73% 75.32% 76.74% 78.00% 79.14% 80.16% 4v 5 0.00000% 0.31% 3.67% 11.01% 19.91% 28.49% 36.04% 42.47% 47.90% 52.49% 56.40% 59.74% 62.64% 65.16% 67.37% 69.32% 71.06% 72.62% 74.02% 75.29% 5e 6 0.00000% 0.05% 1.21% 5.22% 11.72% 19.18% 26.49% 33.13% 38.98% 44.05% 48.45% 52.27% 55.61% 58.54% 61.12% 63.41% 65.46% 67.29% 68.95% 70.45% 6r 7 0.00000% 0.01% 0.34% 2.19% 6.27% 12.05% 18.51% 24.89% 30.82% 36.16% 40.90% 45.10% 48.80% 52.09% 55.00% 57.61% 59.94% 62.04% 63.94% 65.66% 7s 8 0.00000% 0.00% 0.09% 0.81% 3.04% 7.00% 12.19% 17.88% 23.56% 28.92% 33.83% 38.28% 42.27% 45.84% 49.05% 51.93% 54.52% 56.87% 58.99% 60.93% 8

9 0.00000% 0.00% 0.02% 0.27% 1.33% 3.75% 7.51% 12.21% 17.31% 22.43% 27.32% 31.87% 36.04% 39.84% 43.28% 46.39% 49.22% 51.79% 54.13% 56.26% 910 0.00000% 0.00% 0.00% 0.08% 0.53% 1.84% 4.31% 7.87% 12.17% 16.80% 21.46% 25.96% 30.19% 34.12% 37.73% 41.03% 44.06% 46.82% 49.35% 51.67% 1011 0.00000% 0.00% 0.00% 0.02% 0.19% 0.83% 2.30% 4.77% 8.13% 12.08% 16.32% 20.61% 24.78% 28.74% 32.44% 35.88% 39.05% 41.98% 44.68% 47.16% 1112 0.00000% 0.00% 0.00% 0.01% 0.06% 0.34% 1.14% 2.71% 5.14% 8.31% 11.97% 15.89% 19.86% 23.74% 27.46% 30.96% 34.24% 37.29% 40.12% 42.75% 1213 0.00000% 0.00% 0.00% 0.00% 0.02% 0.13% 0.52% 1.44% 3.07% 5.44% 8.43% 11.85% 15.49% 19.19% 22.82% 26.32% 29.65% 32.78% 35.71% 38.45% 1314 0.00000% 0.00% 0.00% 0.00% 0.01% 0.05% 0.22% 0.71% 1.72% 3.38% 5.68% 8.52% 11.72% 15.12% 18.58% 22.00% 25.31% 28.47% 31.47% 34.29% 1415 0.00000% 0.00% 0.00% 0.00% 0.00% 0.02% 0.09% 0.33% 0.91% 1.99% 3.65% 5.88% 8.57% 11.59% 14.78% 18.03% 21.26% 24.40% 27.41% 30.28% 1516 0.00000% 0.00% 0.00% 0.00% 0.00% 0.00% 0.03% 0.14% 0.45% 1.11% 2.23% 3.89% 6.04% 8.60% 11.45% 14.46% 17.53% 20.59% 23.57% 26.45% 1617 0.00000% 0.00% 0.00% 0.00% 0.00% 0.00% 0.01% 0.06% 0.21% 0.58% 1.29% 2.45% 4.09% 6.17% 8.62% 11.32% 14.16% 17.07% 19.97% 22.82% 1718 0.00000% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.02% 0.09% 0.29% 0.71% 1.48% 2.65% 4.27% 6.28% 8.62% 11.18% 13.88% 16.65% 19.41% 18

CalculateTable

0.010 1.000 2.000 3.000 4.000 5.000 6.000 7.000 8.000 9.000 10.000 11.000 12.000 13.000 14.000 15.000 16.000 17.000 18.000 19.000 0.1%

1.0%

10.0%

100.0%

Erlang B chart

123456789101112131415161718

A Erlangs of Offerred Traffic

Lost

Tra

ffic (

%age)

-

GO

S

document.xls

Page 4

CALC_TABLE This macro sits behind the "Calculate table " button#NAME? Calculates the entire spreadsheet#NAME? Returns when complete