PERFORMANCE EVALUATION, VOL.53, NO.1, PP.43-69, 2003.

TITLE: Iterative Disaggregation for a Class of Lumpable Discrete-Time
Stochastic Automata Networks

AUTHORS: Oleg Gusak, Tugrul Dayar, and Jean-Michel Fourneau

ABSTRACT: Stochastic automata networks (SANs) have been developed and 
used in the last 15 years as a modeling formalism for large systems
that can be decomposed into loosely connected components. In this work, 
we concentrate on the not so much emphasized discrete-time SANs. First,
we remodel and extend an SAN that arises in wireless communications. 
Second, for an SAN with functional transitions, we derive conditions 
for a special case of ordinary lumpability in which aggregation is done
automaton by automaton. Finally, for this class of lumpable 
discrete-time SANs we devise an efficient aggregation-iterative
disaggregation algorithm and demonstrate its performance on the SAN
model of interest.

KEY WORDS: Discrete-time stochastic automata networks; Ordinary
lumpability; Iterative disaggregation; Wireless asynchronous transfer
mode system.