Proper Network Design Research Articles

Security Framework for Internet-of-Things-Based Software-Defined Networks Using Blockchain

Presently, trillions of Internet of Things (IoT) devices are in use, with many more projected to join IoT networks in the future. These IoT devices create a massive volume of data, which cannot be transmitted over the network without proper security and privacy. Furthermore, as the amount of information and variety of interconnected devices grows, problems, including excessive response time, bandwidth constraints, and scalability, emerge in proper network design. To solve the constraints of today’s smart cities for next-generation networks, an effective, secure, and scalable distributed framework must be designed bringing computing and storage resources nearer to endpoints. In this article, combining the strengths of software-defined networks (SDNs) and blockchain technology, an innovative adaptable network infrastructure for smart cities is developed. The network is divided into different domains in which SDN will detect potential attacks and transmit the secured data to the blockchain. Our in-depth experimental analysis on performance evaluation show that the proposed framework achieves 12.75% improvement over baseline methodologies.

WAYS OF THE ASTERISK SOFTWARE PBX PROTECTION

Network protection of the Asterisk software PBX widely used in modern info-communication networks is considered. This particular telephone exchange is used to set up telephone communications at the Moscow Technical University of Communications and Informatics. When connecting this software telephone exchange to IP networks, it is necessary to provide its protection to prevent it from being attacked by intruders. The Asterisk IP PBX has powerful protection tools. If properly applied, they can make the protection more reliable than that of some hardware IP PBXs. The protection system can be built in different ways. The most popular ones are the following types of protection: the iptables utility, the development of a proper network design involving the use of VLAN and VPN technologies, the utilization of Fail2Ban log file analyzer. Protection can also be implemented by means of DialPlan and developing a proper configuration of the Asterisk IP PBX.

Engineer design process assisted by explainable deep learning network

Engineering simulation accelerates the development of reliable and repeatable design processes in various domains. However, the computing resource consumption is dramatically raised in the whole development processes. Making the most of these simulation data becomes more and more important in modern industrial product design. In the present study, we proposed a workflow comprised of a series of machine learning algorithms (mainly deep neuron networks) to be an alternative to the numerical simulation. We have applied the workflow to the field of dental implant design process. The process is based on a complex, time-dependent, multi-physical biomechanical theory, known as mechano-regulatory method. It has been used to evaluate the performance of dental implants and to assess the tissue recovery after the oral surgery procedures. We provided a deep learning network (DLN) with calibrated simulation data that came from different simulation conditions with experimental verification. The DLN achieves nearly exact result of simulated bone healing history around implants. The correlation of the predicted essential physical properties of surrounding bones (e.g. strain and fluid velocity) and performance indexes of implants (e.g. bone area and bone-implant contact) were greater than 0.980 and 0.947, respectively. The testing AUC values for the classification of each tissue phenotype were ranging from 0.90 to 0.99. The DLN reduced hours of simulation time to seconds. Moreover, our DLN is explainable via Deep Taylor decomposition, suggesting that the transverse fluid velocity, upper and lower parts of dental implants are the keys that influence bone healing and the distribution of tissue phenotypes the most. Many examples of commercial dental implants with designs which follow these design strategies can be found. This work demonstrates that DLN with proper network design is capable to replace complex, time-dependent, multi-physical models/theories, as well as to reveal the underlying features without prior professional knowledge.

The Potential of Multilayered Hierarchical Nonterrestrial Networks for 6G: A Comparative Analysis Among Networking Architectures

Research for 6th generation (6G) communication currently focuses on nonterrestrial networks (NTNs) to promote ubiquitous and ultrahigh-capacity global connectivity. Specifically, multilayered hierarchical networks, i.e., the orchestration among different aerial/space platforms, including low-altitude platforms (LAPs), high-altitude platforms (HAPs), and satellites cooperating at different altitudes, currently represent one of the most attractive technological options to solve coverage and latency constraints associated with the NTN paradigm. However, several issues still need to be resolved for proper network design. In this work, we evaluate the performance of different multilayered nonterrestrial configurations. We also provide guidelines on the optimal working point(s) for which it is possible to achieve a good compromise between improved system flexibility and network performance with respect to a baseline stand-alone deployment.

Non-Terrestrial Networks in the 6G Era: Challenges and Opportunities

Many organizations recognize non-terrestrial networks (NTNs) as a key component to provide cost-effective and high-capacity connectivity in future 6th generation (6G) wireless networks. Despite this premise, there are still many questions to be answered for proper network design, including those associated to latency and coverage constraints. In this paper, after reviewing research activities on NTNs, we present the characteristics and enabling technologies of NTNs in the 6G landscape and shed light on the challenges in the field that are still open for future research. As a case study, we evaluate the performance of an NTN scenario in which aerial/space vehicles use millimeter wave (mmWave) frequencies to provide access connectivity to on-the-ground mobile terminals as a function of different networking configurations.

Efficient Frequency Reuse for Broadband Wireless Access with Sectored Cells in Offshore Territory

Due to the physical constraint in offshore territory, cell placement to the certain location is not always possible. Because it requires high telecommunication tower or tall building/platform to avoid the curvation of the earth in order to communicate with the distant Customer Premises Equipment (CPE) terminals. Hence, applying the concept of cellular network design to cover all service area in offshore territory without outage area or coverage gap is very difficult to be achieved. Hence, the typical frequency reuse with omni-directional cells in cellular networks is not much practical in this area. In addition, using omni-directional cells can incur lower capacity and shorter transmission range compared to the sectored cells. In this work, efficient frequency reuse is considered in only sectored cells. With proper network design in terms of transmission direction and power, it can guarantee that there is much fewer or possibly no interference among sectors or cells.

Introducing Flexible and Synthetic Optical Networking: Planning and Operation Based on Network Function Programmable ROADMs

Elastic optical networks are envisaged as promising solutions to fulfill the diverse bandwidth requirements for the emerging heterogeneous network applications. To support flexible allocation of spectrum resources the optical network nodes need to be agile. Among the different proposed solutions for elastic nodes, the one based on architecture of demand (AoD) exhibits considerable flexibility against the other alternatives. The node modules in the case of AoD are not hard-wired, but can be connected/disconnected to any input/output port according to the requirements. Thus, each AoD node and the network (fabricated with AoD nodes) as a whole acts like an optical field-programmable gate array. This flexibility inherent in AoD can be exploited for different purposes, such as for cost-efficient and energy-efficient design of the networks. This study looks into the cost-efficient network planning issue for synthetic networks implemented through AoD nodes. The problem is formalized as an integer linear programming formulation for presenting the optimal solution. Furthermore, a scalable and effective heuristic algorithm is proposed for cost-efficient design, and its performance is compared with the optimal solution. The designed networks with AoD nodes are further investigated for a dynamic scenario, and their blocking probability due to limited switching resources in the nodes is examined. To alleviate the blocking performance for the dynamic case, an efficient synthesis strategy along with a scheme for optimal placement of switching resources within the network nodes is presented. Extensive results show that 1) even at high loads, the network with AoD nodes achieves saving of switching modules up to 40% compared to the one with static reconfigurable optical add–drop multiplexers (ROADMs) through a proper network design, 2) by diminishing the spectrum selective switches the overall power consumption of the network decreases by more than 25% for high loads, and 3) for the dynamic scenario the blocking owing to the node modules constraint is alleviated significantly by slightly augmenting the switching devices and optimally deploying them within the network nodes.

Analysis of Estimation Parameter for Energy Efficient in Wireless Sensor Network

In wireless sensor network energy fully depend on battery lifetime. Energy saving by making intelligent importance driven decision about message transmission in self organized method. The selective forwarder is a method which makes intelligent importance driven decision for saving energy. The development of a selective forwarder method based on decision theory which was not stable for network as well as before failure the route, how can recognized the failure route no one knows the idea, for that proposed an approach to develop optimal energy-aware transmission schemes by adaptive selective forwarder for quality of information as well as for stable network. However, in the work include stochastic process and routing protocol depends on parameters like available energy on a node, retransmission a message and message importance. By using these three parameters find out the best performance in network with analysis and comparison of adaptive selective forwarder and local-global forwarder method. The constant threshold values apply for saving energy of each node from source node to sink node for optimal solution in the network. The main focus of work is an analysis the estimated parameter which are used for getting efficient energy according to changing the level of energy of sensor node for increasing the lifetime of battery as well as increasing the lifetime of the network. Also calculate battery lifetime by using Markov decision process rule with proper network design.

Approach for voice quality and throughput estimation in wireless convergent networks

A common communications convergence scenario which is being adopted in personal communications relates to the combination of wireless and cellular networks by the use of multimode terminals. Since most of the wireless networks were initially dimensioned only for data communications, this paper shows how voice over wireless LAN dimensioning could be addressed under the optimal network throughput and the perspective of voice quality, using a simple approach. The maximum number of simultaneous users resulting from throughput is limited by the collisions taking place in the shared medium with the statistical contention protocol. The voice quality is conditioned by the delay and the packet loss in the contention protocol. Both approaches are analyzed within the scope of the voice codecs commonly used in voice over wireless LANs, to conclude that voice dimensioning based on network throughput and voice quality show complementary results. Additionally the use of low rate codecs in voice over wireless LANs is advantageous for the network performance point of view but may produce poor voice quality results. Mid range codecs like G729 could represent a trade-off for quality throughput. For these reasons, voice quality and wireless network throughput have to be taken into account in the network admission control, design and deployment to ensure a satisfactory user experience. The impact of handoff interval of wireless convergent networks on the conversation quality need also be assessed for a proper network design.

Efficient modeling of VBR MPEG-1 coded video sources

The performance evaluation of broadband networks requires statistical analysis and modeling of the actual network traffic. Since multimedia services, and especially variable bit rate (VBR) MPEG-coded video streams are expected to be a major traffic component carried by these networks, modeling of such services and accurate estimation of network resources are crucial for proper network design and congestion-control mechanisms that can guarantee the negotiated quality of service at a minimum cost. The layer modeling of MPEG-1 coded video streams and statistical analysis of their traffic characteristics at each layer is proposed, along with traffic models capable of estimating the network resources over asynchronous transfer mode (ATM) links. First, based on the properties of the entire MPEG-1 sequence (frame layer signal), a model (Model A) is presented by correlating three stochastic processes in discrete time (autoregressive models), each of which corresponds to the three types of frames of the MPEG encoder (I, P, and B frames). To simplify the traffic Model A and to reduce the required number of parameters, we study the MPEG stream at a higher layer by considering a signal, which expresses the average properties of I, P, and B frames over a group of picture (GOP) period. However, models on this layer cannot accurately estimate the network resources, especially in multiplexing schemes. For this reason, an intermediate layer is introduced, which exploits and efficiently combines information of both the aforementioned layers, producing a model (Model B), which requires much smaller number of parameters than Model A and simultaneously provides satisfactory results as far as the network resources are concerned. Evaluation of the validity of the proposed models is performed through experimental studies and computer simulations, using several long duration VBR MPEG-1 coded sequences, different from that used in modeling. The results indicate that both Models A and B are good estimators of video traffic behavior over ATM links at a wide range of utilization.

Minimal cost coverage planning for single frequency networks

OFDM based single frequency networks (SFNs) have been standardized for terrestrial broadcasting systems, for digital audio broadcasting (DAB) as well as for digital video broadcasting (DVB). Due to the multipath tolerance of the OFDM scheme, the receiver is able to combine signals coming from several transmitters, despite of the varying propagation delays, i.e., heavy artificial multipath propagation. In order to take full advantage of the diversity gain provided by the SFN architecture, proper network design is required. We focus on the cost efficient design of an SFN providing broadcasting services over a predefined service area with requirements both on the received signal quality and on the allowable interference level experienced by existing services in the same spectrum. We formulate the problem as a discrete optimization problem, where the network design parameters such as power, antenna heights and transmitter locations are the decision variables. The general stochastic optimisation algorithm simulated annealing has been adapted for solving the above problem. The novelty of our method is that cost factors and interference constraints are embedded in the optimisation procedure. Through numerical examples we demonstrate that significant reduction in network cost can be achieved by our approach.

The role of the elastic rebound theory in design and evaluation of deformation surveys

The elastic rebound theory of shallow tectonic earthquakes proposed by H.F. Reid as a comprehensive description of deformation in time along an active fault is analysed from a geodetic point of view. The relationship between the different stages of deformation and the epochs of geodetic measurements emphasizes the importance of proper network design, because the three basic hypotheses investigated predict displacements characterising the process in different zones of the network. The proper choice of datum stations according to these hypotheses and the similarity transformation applied for generalized, free network determination proved to be a time-saving approach. The proposed procedure may be advantageous when the noise levels of observations are near to the expected deformations.

Coding with Linear Systems

Message transmission over a noisy channel is considered. Two linear networks are to be designed: one being used to treat the message before transmission and the second to filter the treated message plus channel noise at the receiving end. The mean-square error between the actual transmission circuit output and the delayed message is minimized for a given allowable average signal power by proper network design. Numerical examples are given and discussed.