ErlangB

ErlangB[c,a]

computes the Erlang B loss probability for an M/M/c/c queue.

Details

Examples

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Basic Examples  (2)

Compute a loss probability using ErlangB:

Obtain the same result using Probability:

Plot for a different number of servers c:

Scope  (4)

Use exact values for the parameters:

Machine precision:

Higher precision:

Symbolic parameters:

Applications  (2)

A company has five 1 Mbps lines to carry video conferences between two company sites. Suppose that each video conference requires 1 Mbps and lasts for an average of one hour. Assume that requests for video conferences arrive according to a Poisson process with a rate of three calls per hour. Find the probability that a call request is blocked due to lack of lines:

A modem pool consists of four modems and the offered traffic intensity is 2 Erlangs. Find the probability that a connection fails due to blocking:

Blocking probability with six modems:

Properties & Relations  (3)

ErlangB gives the loss probability for an M/M/c/c queue:

ErlangB satisfies a nonlinear difference equation:

ErlangB is related to ErlangC:

Introduced in 2012
 (9.0)