Lecture 12

# Mm1 model innite servers this is the limiting case of

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Unformatted text preview: hange in the average call holding time can also impact on network call blocking performance (a phenomenon observed with more users using the telephone for Internet dial-up). Now, if we wanted to keep the call blocking at the initial value of 0.018, then for 50 erl of load, we will need at least 61 channels! (This is obtained using the Inverse Erlang-B formula discussed later.) 15. M/M/1 model: inﬁnite servers This is the limiting case of M/M/m model with m = j ,1 = jj Thus, From the condition, P j j j = 1 2 ::: j = =j j1! 0 = 1, 1. The balance equation reduces to j = 1 2 ::: we obtain that 0 = exp,=: Thus, j = =j exp,!= j j=0 12 ::: Thus, in steady-state, the number in the system is Poisson distributed with parameter number in the system (i.e. number of busy channels) is =. The average  N = : However, we know that this nothing but a for erlang offered load. Thus, this gives us another interpretation for the deﬁnition of offered load in erlangs: the average number of busy servers (channe...
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## This document was uploaded on 03/19/2014 for the course CS 6030 at Western Michigan.

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