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Large-scale network simulations are resource and time intensive tasks due to a
number of factors i.e., setup configuration, computation time, hardware, and en
ergy cost. These factors ultimately force network researchers to scale-down the
scope of experiments, either in terms of Simulation Entities (SEs) involved or
in abridging expected micro-level details. The Cloud technology facilitates re
searchers to address mentioned factors by the provisioning of Cloud instances on
shared infrastructure. In this thesis, an academic Cloud SIM-Cumulus targeting
the research institutions is proposed. The thesis is divided into three parts, each
part discussing the contributions achieved in thesis.
The first part of this thesis discusses the design and implementation of SIM
Cumulus academic Cloud framework for the provisioning of Network-Simulation
as-a-Service (NSaaS). SIM-Cumulus provides the framework of Virtual Machine
(VM) instances specifically configured for large-scale network simulations, with
the aim of efficiency in terms of simulation execution time. The performance of
SIM-Cumulus is evaluated using large-scale Wireless Network simulations that
are executed sequentially as well as in parallel. Simulation results show that
SIM-Cumulus is beneficial in two aspects i.e., (i) promotion of research within
the domain of computer networks through configured Cloud instances of network
simulators (ii) consumption of considerably fewer resources in terms of simula
tion elapsed time and usage cost. The execution of simulation in parallel involves
the partitioning of simulation model into several components and each compo
nent is assigned to separate execution units (Logical Processes (LPs)). Each LP
is comprised of a set of SEs that can interact with local as well as remote SEs.
However, the remote communication among SEs and synchronization manage
ment across LPs are the two main issues related to the parallel and distributed
executions of large-scale simulations. A number of migration techniques are used
to mitigate the problem of high remote communication and lead to a reduction
in remote communication among SEs. However, most of the existing migration
strategies result in higher number of migration which lead to higher computation overhead. The second part of the thesis contributes Migration-based Adaptive
Heuristic Algorithm (known as MAHA). MAHA provides dynamic partitioning of
the simulation model based on runtime dynamics of the wireless network simula
tions. The proposed algorithm uses an intelligent heuristic for migration decision
in order to reduce the number of migrations with an ultimate goal to achieve bet
ter Local Communication Ratio (LCR). The proposed algorithm is better in terms
of achieving improved LCR with reduced number of migrations as compared to
the existing technique(s). The third contribution of this thesis is related to imple
mentation of adaptive SIM-Cumulus (A-SIM-Cumulus) that integrates Advanced
Runtime Infrastructure System (ARTIS) and Generic Adaptive Interaction Archi
tecture (GAIA) with the SIM-Cumulus framework. To obtain an insight into the
performance gain, the simulation has been performed multiple times with different
configurations and execution environments. The obtained results assert that the
proposed algorithm significantly reduces the number of migrations and achieves
a good speedup in terms of execution time for parallel (i.e., both multi-core and
distributed) simulations on the A-SIM-Cumulus Cloud. |
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