JOINT ICTP/SISSA STATISTICAL PHYSICS SEMINAR: "Statistical mechanics of congestion"

[statphys]

JOINT ICTP/SISSA STATISTICAL PHYSICS SEMINAR

Tuesday, 13 October 2009   -    11:00 hrs

Lecture Room D
SISSA Main Building

Daniele DE MARTINO
(S.I.S.S.A. - Trieste)

"Statistical mechanics of congestion"

Abstract
Within the framework of a simple model, we are able to study the overall 
performance of a given informational network, depending on its uptaking 
as well as on the level of traffic control. Simple enough to get 
analytical results, it  still shows a very rich phenomenology, 
presenting continuous, discontinuous as well as hybrid phase transitions 
between a free-flow phase and a congested phase, critical points and 
different scaling behaviors in the system size. We find that traffic 
control improves global performance, enlarging the free-flow region in 
parameter space only in heterogeneous networks. Traffic control 
introduces non-linear effects and, beyond a critical strength, may 
trigger the appearance of a congested phase in a discontinuous manner. 
The model also reproduces the cross-over in the scaling of traffic 
fluctuations empirically observed in the Internet.
Ref:
PRE 79, 015101(R) (2009)
Jstat P08023 (2009)