A most simple and good example of network topology is LAN [3-4, 8-9]. Where it LAN has one or more physical links to other devices in the network. In recent days there are basically two basic categories of network topologies, they are Physical topologies [8-9] and Logical topologies [8-9]. Physical Network Topology emphasizes the hardware associated with the system including workstations, remote terminals, servers, and the associated wiring between assets. Conversely, Logical Network Topology emphasizes the representation of data flow between nodes. A brief view of various commonly used topologies are presented and discussed in this paper.
To keep up with the rapid development of railway and meet the high demand for communication business in China, Global System for Mobile Communications-Railway (GSM-R) based on General Packet Radio Service (GPRS) ahead of Europe has been developed. However, the current datacommunication mode of GPRS using TCP/IP has some disadvantages, such as poor mobility, lack of security etc. For this reason, there are some problems for GSM-R, like handover, which makes communication service quality undesirable. Named DataNetworking focuses on named data, adopts data-facing communication mode, and does not care where the contents are stored but the contents themselves. It can effectively solve the problems caused by TCP/IP. In this paper, a new high-speed railway communication system with Named DataNetworking (NDN) named NDN-GSM-R is proposed. Two simulations, called transmission interference time and end-to-end transmission delay of NDN-GSM-R, have been conducted. The simulation results show that NDN-GSM-R has better performance in high-speed mobile communication
Recent research involves the impact of Cloud computing on Vehicular Adhoc Networks. To improve the traffic safety and to provide computational services to road users, a new cloud computing model called VANET- Cloud is proposed. VANET cloud challenges include security and privacy issues that includes data integrity, data access, data loss and protecting the confidential data of users. The data centers in the cloud consume large amount of energy. So, alternative servers like onboard computers in vehicles can be used. Vehicles spend limited life time in cloud network. There should be continuous, efficient and secured communication between the VANET vehicles (nodes) as VANET Cloud entities. Efficient routing protocol should be developed to overcome the above issue. 
Abstract—In order to solve the shortcomings of the landslide monitoring technology method, a set of landslides monitoring and early warning system is designed. It can achieve real-time sensor data acquisition, remote transmission and query display. In addition, aiming at the harsh environment of landslide monitoring and the performance requirements of the monitoring system, an im- proved minimum hop routing protocol is proposed. It can reduce network ener- gy consumption, enhance network robustness, and improve node layout and networking flexibility. In order to realize the remote transmission of data, GPRS wireless communication is used to transmit monitoring data. Combined with remote monitoring center, real-time data display, query, preservation and landslide warning and prediction are realized. The results show that the sensor data acquisition system is accurate, the system is stable, and the node network is flexible. Therefore, the monitoring system has a good use value.
The visible light is the form in which the electromagnetic radiation with wavelengths in particular range is interrupted by human brain. The visible spectrum covers the wave lengths from 380 nm to 750 nm. Visible light communication (VLC) is an evolving communication technology for short range applications. Exploiting recent advances in the development of high-power visible-light emitting LEDs, VLC offers an energy-efficient, clean alternative to RF technology, enabling the development of optical wireless communication systems that make use of existing lighting infrastructure.
Since vehicular network is essentially a network of ma- chines that are communicating without human intervention, the process can also be described as Machine-to-Machine (M2M) communications . Specifically, the recent evolving LTE-Advanced standards support machine-type communica- tions (MTC) which allows large-scale devices autonomously exchanging information. Consequently, MTC enabled LTE- A may potentially facilitate many vehicular applications, like floating car data (FCD), vehicle diagnosis and fleet manage- ment . In , a use case of dynamic traffic forecast was investigated which uses on-board sensors as an information source. To reduce the impact of MTC traffic on the QoS of human-to-human communications, this paper presented a channel-aware transmission strategy wherein vehicles prob- abilistically transmit FCD based on the measured signal-to- noise ratio.
This paper has investigated a new robust information surveillance problem under the UAV-enabled CR net- work. A proactive eavesdropping scheme has been con- sidered to monitor the suspicious transmission between the suspicious UAV transmitter and the ground receiver via jamming. The full-duplex legitimate monitor adap- tively optimizes the transmission beamforming vector to maximize the eavesdropping rate, which is formulated as a non-convex semi-infinite optimization problem. To solve it, we have transformed it into a problem with finite constraints, then the optimal solution in low-complexity were proposed. The numerical results show the superi- ority of our proposed schemes in UAV-enabled wireless communicationnetworking.
with a network infrastructure. This is particularly valid for wireless LANs, which show a special arrangement of difficulties to IT and security experts. Notwithstanding the run of the mill issues that new network and device technologies cause, including inconsistencies and continuous help issues, non-secure wireless LANs can uncover an association's network traffic and assets to unapproved pariahs. Such people may catch data and endeavour network-based assets, including Internet access, fax servers, and plate stockpiling. Wireless LAN radio signals can stretch out past the expected edge and "break" through the physical limits of a story or building. As these transmissions saturate normal, open, or private areas, for example, streets, parking areas, and different structures, they may fall prey to "wardriving" or a "drive-by hacking" attack .
The main issue with Data Centers, with respect to Green Networking, is their ineﬃcient use of electrical power by the Data Center components. In addition, electrical power generation from coal becomes a critical issue. Data centers store a vast amount of data used on a daily basis by users, companies, government, and academia. As the demand for data has increased so has the size of Data Centers. Consequently, the power consumed has also increased. In 2003, a typical Data Center consumed about 40 Watts per square foot energy, and in 2005 this figure has been raised to 120 Watts/sq ft energy , and it is anticipated that this figure will continue to rise. Rack density, which is number of devices per rack, within the Data Center has also increased. This increase in rack density directly increases the heat load, which needs to be dissipated in form of cooling. Some Data Centers have got to a point where the local electricity supplier cannot supply further electricity. The typical Data Center consists of blade servers, storage devices, and multiprocessor servers. These servers are housed in racks placed in rows on a raised floor. The raised floor allows for power distribution, data cable distribution, and cooling ducts. In a recent report, Gartner  predicts that in the future (we are already in 2009!) many organizations will spend more on annual IT energy bills than they will be spending on servers.
With rapid increase in user equipment, the bandwidth requirement is also increased to enable the ﬂow of large amount of data . The exponential increase is expected in a number of devices such as HD TVs, laptops, smart phones, home appliances, video surveillance systems, sensors, wearable devices, cameras and robots in near future. 5G technology promises the required data rate and bandwidth for such applications  such that 5G mobile communication is expected to assist large number of real time applications, tactile internet  and services with diﬀerent levels of quality (QoS) (like, bandwidth, jitter, packet delay, latency and packet loss) and quality of experience (like network providers and users). The high-speed data transfer, zero latency and ubiquitous connectivity are the main characteristics of 5G technology. 5G technology will interconnect every electronic and digital appliance/services like temperature maintenance, printers, air conditioners, refrigerators, LED’s door locks, microwave oven,
The gateway buoy (GB) act as an intermediate which communicate with all the sensor nodes in underwater which in turn transmit the acoustic signal to the satellite . The GB improves the lifetime of the network. But if GB is not present in ocean, then the satellite link acts as an alternative way of communication. GB can be fixed or mobile. If GB is fixed at a suitable position and anchored at the ocean floor, it has direct communication to the server. In contrast, if GB is mobile then the communication is done through satellite. Also, underwater sensor nodes can be fixed or mobile. Sensor nodes are anchored or moored at the seabed in case of fixed sensors whereas other sensors are moving in a vertical position at the different levels in the ocean. In underwater sensor networks we require high power due to farthest distance of the sensors whereas in terrestrial network the power required for the communication is low. Signals in underwater communication are mode distorted, faded and very complex. A very complex signal is processed at both ends.
A conditional probability (CP) examines the probability of an event occurring given another event has occurred. For example, if the health care provider asks a patient about pain, the patient will usually describe their pain in more detail. On the other hand, sometimes patients bring up topics such as sexuality that providers may want to avoid discussing. It requires discrete not continuous variables and a method to identify time periods. Using timestamps from audiofiles, discrete information about the occurrence of specific desired behaviors can be linked with visit outcomes. Conclusions may be confounded by the fact that explanatory variables may be correlated with other explanatory variables. Simple tests, such as t-tests and Fisher’s exact test could explore the difference in mean or percentage between predefined groups, for example, length of visit or percentage referral for counseling between female and male providers. Such direct analyses are useful during exploratory and descriptive studies, but not for more complex models of communication processes where multiple variables may predict a single outcome (Figure 2).
Named DataNetworking (NDN) is an as of late proposed new Internet architecture. By naming information rather than location, it changes the essential system service abstraction from "transmitting packets to offered destinations" to "retrieving information of given names." This major change makes a plenitude of new opportunities as well the same number of scholarly difficulties in application advancement, system routing and sending correspondence security and protection. In this study, researchers will propose a new architecture of NDN with smart and automated forwarding information based which is more versatile and proficient.
Abstract — Many people are always on move. While many of those spend a many days away from their home but they don’t have any control over the home appliances in their homes. Some devices may be remains switched on or some other appliances have to be switched on at some interval of time e.g electric motor on well. If these devices cannot be controlled in good manner then they are responsible to create lot of energy crisis . So as to overcome from this scenario I proposed an internet based home automation system which will helps any end user to remotely manage their appliances from anywhere, anytime. In this paper we have developed a Home Automation system that employs the integration of multi-touch mobile devices, cloud networking, wireless communication, and power-line communication to provide the user with remote control of various lights and appliances within their home. This automation system differs from other systems by allowing the user to operate the system without the dependency of a mobile carrier or Internet connection via the in-home wireless remote.