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Network Function Virtualization (NFV) can provide the resource according to the request and can improve the flexibility of the network. It has become the key technology of next generation communication. Resource scheduling for virtual network function service chain (VNF-SC) mapping is the key issue of the NFV. A virtual network function service chain placement multi-objective optimization model and algorithm based on improved genetic algorithm is proposed. Firstly, a multi-objective optimization model, which minimizes deployment cost, transmission delay and maximizes the load balance, is established. On this basis, an improved genetic algorithm based on MOEA/D is proposed to solve the established multiobjective model. In this algorithm, the combination scheme and mapping scheme of the service request are coded by the two-level coding method in the mapping process, and then the improved sparrow search algorithm is used to obtain the service function chain deployment scheme of the request and calculate the mapping weight. In addition, an efficient individual generation strategy is proposed to generate some superior individual. Finally, some simulation experiments are conducted and the experimental results show that the algorithm can effectively reduce deployment cost and transmission delay than the compared algorithm. [ABSTRACT FROM AUTHOR]

Sensor data exchanges in IoT applications can experience a variable delay due to changes in the communication environment and sharing of processing capabilities. This variability can impact the performance and effectiveness of the systems being controlled, and is especially reflected on Age of Information (AoI), a performance metric that quantifies the freshness of updates in remote sensing. In this work, we discuss the quantitative impact of activation and propagation delays, both taken as random variables, on AoI. In our analysis we consider an offline scheduling over a finite horizon, we derive a closed form solution to evaluate the average AoI, and we validate our results through numerical simulation. We also provide further analysis on which type of delay has more influence on the system, as well as the probability that the system fails to deliver all the scheduled updates due to excessive delays of either kind. [ABSTRACT FROM AUTHOR]

In this paper, the stochastic stabilization problem of uncertain networked control systems involving Takagi–Sugeno (T–S) fuzzy model, transmission delays and external disturbances is investigated, where the random network-induced delays are modeled as Markov chains. Firstly, by combining T–S fuzzy model with fuzzy PID controller, the uncertain networked control systems with random communication delays and external disturbances are modeled. Then, the uncertain networked control system is simplified through a mathematical method, and the stabilizing controller is derived for the uncertain networked control systems by using Lyapunov functional and linear matrix inequality. Finally, simulation results are presented to verify the effectiveness and availability of the developed results. [ABSTRACT FROM AUTHOR]

This paper works with the simulation of T-CONT allocation and delay analysis in passive optical networks PON. Building our networks with the PON technology we can achieve increased data rates, however we need to ensure that the idle gaps between the particular transmissions are minimal. The primary method for the upstream time slot allocation in passive optical networks is via Multi Point Control Protocol. The baseline standard of this protocol clearly defines the use o f the REPORT and GATE control messages. The two optical network elements used here, the optical network unit ONT and the optical line termination OLT, located at the central office CO, can be scheduled to allocate the time slots. Using the control messages, a more accurate scheduling algorithm can be developed, hence we can directly improve the utilization of the bandwidth as well. In this work, we introduce the basic topology of the passive optical networks, how PON works and what basic principles o f bandwidth allocation have been applied. Subsequently, we suggest a selection of methods for time slot allocation and we make an analysis on the achieved results. Our main focus is on the system load, transfer delay and the analysis of the effectivity. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a high-speed low-power comparator, which is used in a 2 Gsps, 8 bit Flash ADC, is designed and simulated. Based on 0.18 um TSMC CMOS process model, the comparator circuit is simulated with a 1.8V power supply in Cadence environment. The result shows that it can work at a 2GHZ clock frequency, and the dynamic power consumption is only 1.2mW, with 123.5ps transmission delay. In addition, the average offset voltage of this comparator is only 676.3uV, which can meet the requirements of an 8-bit Flash ADC. [Copyright &y& Elsevier]

• Designs a lightweight authentication and key management to provide a secure transmission between the computing devices. • Limits the use of computation operations to improve performance efficiencies namely transmission delay and throughput rate. • Uses static and continuous user authentication to generates a key token dynamically between the peer computing devices. • Adopts a token technique to analyze the battery capacities of the devices that continuously senses the device activities. • Conducts formal and informal analysis to verify the security robustness and time consumption of L-AKM. Internet of Things (IoT) utilizes an intelligent technique to facilitate the design and development of smart-urban projects. As the smart devices have limited battery sources, IoT services should initiate its setup with low-power consumption. Most of the existing approaches use Long Range Wide Area Network (LoRa-WAN) as a media access layer. It provides a long-range communication between the smart devices and application systems over Low Power Wide Area Network (LP-WAN). However, it fails to achieve end-to-end security and perfect secrecy to guarantee access security of the channels. An objective of mobile-sink is to solve the problem of data confidentiality, mutual authentication, session-key agreement, and preventing potential attacks. Thus, this paper presents a lightweight based authentication and key management (L-AKM) scheme for Smart IoT-Assisted Systems. To accomplish the key objectives of L-AKM, a lightweight continuous authentication was preferred that adopts the valid authentication period and continuous user authentication session to speed up the authentication process. The performance analysis proves that the L-AKM scheme achieves better security efficiencies to resist various potential attacks such as forgery, replay, password guessing, etc. However, the experimental analysis shows that the proposed L-AKM consumes more transmission delay and throughput rate due to extra authentication phases. [ABSTRACT FROM AUTHOR]