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In digital networks of integrated service ISDN loading multimedia on port, such as the voice, the data, video and etc., are transferred in the form of packages. In system of package switching of standard X.25, the package has variable length while in system ATM for broadband network ISDN the package becomes a cell of constant length. As the packaged process has in steps raging nature superposition process (imposed one on another) many sources becomes not pulsing. Therefore process MMPP was widely adopted at research of raging streams in networks of package switching.
The model of the packaged voice (video) is shown on fig. 15 as relay (ON-OFF model).
For a single sound source believe that the periods of the speech statement and silence are distributed экспоненциально with average sizes a-1 and b-1, accordingly, and packages (cells) are generated during T during the speech statement. From here define rate of receipt l, SCV Ca2 and asymmetry Sk.
Raging streams can be characterised indexes of a dispersion and asymmetry of number of the packages arriving for an interval of time (0, t]. Indexes are entered as the relation of the corresponding central moments to a population mean of arriving packages in time t. For dispersion and asymmetry indexes the law of preservation of indexes is carried out: indexes of an individual relay source are equal to corresponding indexes of superposition of process of receipt of packages from n independent sources.
The raging stream (from n independent sources) can be approximated superposition of packages diphasic process MMPP. Thus unknown parametres of process MMPP (rates of receipt of calls in different phases and distributions of time of life in different phases) are defined on the measured indexes of a dispersion and asymmetry of a raging stream.
The mixed models of raging loading of port from n independent sources approximate 2-phase process MMPP. We believe that superposition n individual 2-phase processes MMPPi forms mixed 2n-phase process MMPP which we approximate again diphasic process MMPP. Familiarise with model MMPP+M/G/1, study indicators of quality of the one-linear mixed system of service of the raging traffic (individual average waiting times on loadings MMPP and Poisson, accordingly; an average virtual waiting time of process MMPP in a phase l, l=1, 2; averages virtual and valid waiting times for the mixed loading with priority schemes; individual speed of loss of cells on loadings MMPP and Poisson, accordingly; virtual speed of loss of cells of process MMPP in a phase l, l=1, 2).
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