  Probabilistic broadcast has been widely used as a flooding optimization
mechanism to alleviate the effect of broadcast storm problem (BSP) in mobile ad
hoc networks (MANETs). Many research studies have been carried-out to develop
and evaluate the performance of this mechanism in an error-free (noiseless)
environment. In reality, wireless communication channels in MANETs are an
error-prone and suffer from high packet-loss due to presence of noise, i.e.,
noisy environment. In this paper, we propose a simulation model that can be
used to evaluate the performance of probabilistic broadcast for flooding in
noisy environment. In the proposed model, the noise-level is represented by a
generic name, probability of reception (pc) (0<=pc<=1), where pc=1 for
noiseless and <1 for noisy environment. The effect of noise is determined
randomly by generating a random number \zeta (0<=\zeta<1); if \zeta<=pc means
the packet is successfully delivered to the receiving node, otherwise,
unsuccessful delivery occurs. The proposed model is implemented on a MANET
simulator, namely, MANSim. The effect of noise on the performance of
probabilistic algorithm was investigated in four scenarios. The main
conclusions of these scenarios are: the performance of probabilistic algorithm
suffers in presence of noise. However, this suffering is less in high density
networks, or if the nodes characterized by high retransmission probability or
large radio transmission range. The nodes' speed has no or insignificant effect
on the performance.
