Modeling of Data Communication Networks using Dynamic Complex Networks and its Performance Studies

This chapter studies the problem of decentralized resource allocation among competing users in communication networks. The growth in the scale of communication networks and the newly emerging interactions between administrative domains and end-users with different needs and quality of service requirements necessitate new approaches to the modeling and control of communication networks that recognize the difficulty of formulating and implementing centralized control protocols for resource allocation. The current research in this area has developed a range of such approaches. Central to most of these approaches is the modeling of end-users and sometimes also of service providers as self-interested agents that make decentralized and selfish decisions. This research has two important implications:

Communication networks are complex information systems influenced by a vast amount of factors. It is critically important to forecast the paths that data take to verify the network, check its security and plan its updates. Model allows exploring processes that take place in the network without affecting performance and availability of a real network itself. With modelling it becomes possible to investigate the results of infrastructural changes introduced to the network before actually implementing them. It is important to be able to formally convert real network description into the model definition which preserves all data that is significant for network operation and skip data which is not. Outlining the rules for such conversion and using a limited set of basic functional components provide the ground for automatic model creation for the network of different levels of complexity.Proposed approach to modelling of communication networks is based on decomposition of the overall function of every particular real network component into a set of functions that belong to some predefined basic set. Functions of the basic set include L3 routing, L2 switching, packet filtering, NAT, etc. Model of a real network component is defined as a group of functional nodes each of which implements some function from the basic set.Configuration and current state of network components that influence its operation are also decomposed into elements each of which relates to some particular functional node. Configuration of network components is modelled as a set of configuration storage elements and current state is modelled as a set of current state storage elements.Links that connect real network components and links that connect functional nodes in the model are presented as singledirection channels that implement propagation of L2 frames thus simplifying the model due to excluding physical layer (L1) from the scope.Using the proposed approach to modelling may allow to formalize conversion of a real network descrip- tion to a model thus making automated modelling possible. By using a sufficient basic set of functional nodes it is possible to model the network containing components of any complexity level.

Future smart grids represent interdependent cyber-physical systems that involve multiple interactions between a power grid and a communication network. Such a mutual dependence increases the risk of large-scale cascading failures. Thus, it is important to conduct a joint vulnerability analysis. Unfortunately, existing works failed to identify the combination of power nodes and communication nodes that present the greatest damage impact. In this article, we first present a model that captures the interdependence between the two subsystems using stochastic geometry; then, we conduct a joint vulnerability analysis. We propose an attack strategy that targets the most influential nodes in both subsystems. We show that, based on six joint targeted nodes, this strategy presents a comparable and, in some cases, larger damage impact compared to the traditional exhaustive search attack and with very low complexity. Our investigations reveal that 1) the proposed joint attack strategy presents a large damage impact at a significantly small simulation runtime and 2) attacking the most influential communication nodes solely or the most influential power nodes solely achieves a comparable damage impact to that of the proposed joint attack.

This paper extends previous research efforts related to the simulation performance modelling and analysis of satellite communication networks. Specifically, the use of low earth orbit (LEO) satellite networks for personal communications is examined. Six different satellite constellation configurations are investigated in a packet-switched operating environment. Performance metrics examined are the end-to-end packet delay and the utilization of satellite channels in the dynamic environment. Realistic and accurate models of the physical satellite network and its terrestrial transmitters require that numerous operating characteristics and assumptions be specified. These are based on proposed design requirements of commercial systems, such as Iridium. Via the use of simulation, we show the relative delay and utilization performance of differing satellite network architectures. From these simulation models, mathematical metamodels are derived for the system delays. These innovative models are used to predict the delay performance of different network architectures not previously simulated. Comparison of these metamodels with simulation results show that metamodels provide an accurate means for performance prediction. Copyright © 1999 John Wiley & Sons, Ltd.

The scope of complex dynamical networks (CDNs) with dynamic edges is very wide, as it is composed of a class of realistic networks including web-winding systems, communication networks, neural networks, etc. However, a classic research topic in CDNs, the synchronization control problem, has not been effectively solved for CDNs with dynamic edges. This paper will investigate the emergence mechanism of synchronization from the perspective of large-scale systems. Firstly, a CDN with dynamic edges is conceptualized as an interconnected coupled system composed of an edge subsystem (ES) and a node subsystem (NS). Then, based on the proposed improved directed matrix ES model and expanded matrix inequality, this paper overcomes the limitations of coupling term design in node models and the strong correlation of tracking targets between nodes and edges. Due to the effect of the synthesized node controller and the auxiliary effect of the ES, state synchronization can be realized in the CDN. Finally, through simulation examples, the validity and advantages of our work compared to existing methods are demonstrated.

Epigenetic communication through histone and cytosine modifications is essential for gene regulation and cell identity. Here, we propose a framework that is based on a chromatin communication model to get insight on the function of epigenetic modifications in ESCs. The epigenetic communication network was inferred from genome-wide location data plus extensive manual annotation. Notably, we found that 5-hydroxymethylcytosine (5hmC) is the most-influential hub of this network, connecting DNA demethylation to nucleosome remodeling complexes and to key transcription factors of pluripotency. Moreover, an evolutionary analysis revealed a central role of 5hmC in the co-evolution of chromatin-related proteins. Further analysis of regions where 5hmC co-localizes with specific interactors shows that each interaction points to chromatin remodeling, stemness, differentiation, or metabolism. Our results highlight the importance of cytosine modifications in the epigenetic communication of ESCs.

Based on the data in real combat games, the combat System-of-Systems is usually composed of a large number of armed equipment platforms (or systems) and a reasonable communication network to connect mutually independent weapons and equipment platforms to achieve tasks such as information collection, sharing, and collaborative processing. However, the generation algorithm of the combat system in the existing research is too simple and not suitable for reality. To overcome this problem, this paper proposes a communication network generation algorithm by adopting the joint distribution strategy of power law distribution and Poisson distribution to model the communication network. The simulation method is used to study the operation under continuous attack on communication nodes. The comprehensive experimental results of the dynamic evolution of the combat network in the battle scene verify the rationality and effectiveness of the communication network construction.

This manuscript explores the analysis of passivity and synchronization criteria for a complex fractional-order dynamical network model with derivative couplings and time-varying delays. The passivity problem of the proposed network model is deduced using various inequality methods and presented as a linear matrix inequality. To ensure complete synchronization for a fractional-order complex dynamical network with derivative couplings (CDNMDC), we derive suitable criteria using an adaptive feedback control method. Additionally, we investigate the synchronization criterion of these complex networks while accounting for parameter uncertainties. Finally, we provide an example to demonstrate the effectiveness of the proposed solutions.

In order to improve the security of low-latency cluster dispatching communication network nodes, this paper proposes a security situation assessment method of low-latency cluster dispatching communication network nodes based on grey relational model. The security situation assessment model of low-delay cluster scheduling communication network nodes is constructed, and the comprehensive risk index is introduced as the three-layer assessment index of low-delay cluster scheduling communication network nodes. Based on the analysis of load loss probability and expected response characteristics of insufficient packet loss load in communication transmission, the reliability index calculation system of low-delay cluster scheduling communication network node scheduling is established. By introducing expected load reduction parameters, the frequency characteristics of node scheduling security in low-delay cluster scheduling communication network are monitored. Based on the average sustained risk index evaluation of load reduction, the security permission conditions of node scheduling in low-delay cluster scheduling communication network are established. The network transmission load control is carried out by using grey correlation scheduling model. The node control model of low-delay cluster scheduling communication network is constructed by combining risk assessment and load parameter detection. The learning control of node security situation assessment is realized by using Cyber-net and unsupervised learning methods. The node security situation assessment of low-delay cluster scheduling communication network nodes is realized through access and decentralized scheduling. Tests show that this method has high accuracy in evaluating the security situation of nodes in low-delay cluster dispatching communication networks, and has strong completeness and reliability in grid-connected control of communication networks.

The Block Oriented Network Simulator (BONeS) DESIGNER provides a graphical environment for modeling and discrete-event simulation of computer and communication networks, distributed computer systems, and computer architectures. DESIGNER uses a hierarchical data flow block diagram modeling paradigm which provides for definition of data structures that flow between blocks. This modeling paradigm provides sufficient flexibility to model and simulate a broad range discrete-event systems, including computer network and distributed processing systems. >

Queuing networks models are widely used as important tools for the performance modeling and evaluation of both computer systems and communication networks. Exact solutions are generally not attainable except for some special cases. Consequently, numerical techniques and analytic approximations are needed for the study of queuing networks with bursty traffic. This paper presents the performance modeling and evaluation of general packet radio service (GPRS) for wireless global system for mobile telecommunication (GSM) cells with bursty multi-class traffic under a partial sharing scheme (PSS). The model has been developed using a new powerful tool, MOSEL (Modeling, specification and evaluation language), which is based on numerical methods and the Petri-nets. The proposed model has been validated against simulation and those developed using maximum entry (ME), a well established methodology for approximate solutions. Numerical results demonstrate the credibility of our models.

MOGUL (model generator with user leadthrough) and REGAL (report generator and lister) are easy-to-use, powerful tools for simulation modeling of computer systems and communication networks. Using MOGUL and REGAL along with Wolverine Software's GPSS/H and PROOF, the user gets a complete environment for building computer system and network models, running simulation experiments, and evaluating results. Animation of the graphical output is supported. Graphical input specification of the processors, devices, and networks in a model will also be possible in an upcoming release. >

Localization of information on communication networks of an open-source online community

Collaborative optimization of distribution network and 5G base stations considering its communication load migration and energy storage dynamic backup flexibility

In the paperwork, a review of programs used to model communication networks has been made. The review is divided into three major groups: programs for modeling of IP-based networks, programs for modeling of any telecommunication networks and programs for modeling of cloud infrastructures. For each of the groups one program is proposed, indicating why it is selected. The chosen programs are: GNS3 (IP network simulator), Riverbed Modeler academic edition (Telecommunication network simulator) and GreenCloud. With each of the proposed programs, simulation models of communication networks have been developed. Some of the results and capabilities of each of the programs are shown.