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Network Traffic Simulation
Network traffic simulation is a process used in telecommunications engineering to measure the efficiency of a communications network. Overview Telecommunications systems are complex real-world systems, containing many different components which interact, in complex interrelationships.Flood, J.E. ''Telecommunications Switching, Traffic and Networks'', Chapter 4: Telecommunications Traffic, New York: Prentice-Hall, 1998. The analysis of such systems can become extremely difficult: modelling techniques tend to analyse each component rather than the relationships between components.Penttinen A., ''Chapter 9 – Simulation'', Lecture Notes: S-38.145 - Introduction to Teletraffic Theory, Helsinki University of Technology, Fall 1999. Simulation is an approach which can be used to model large, complex stochastic systems for forecasting or performance measurement purposes.Kennedy I. G., ''Traffic Simulation'', School of Electrical and Information Engineering, University of the Witwatersrand, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that feasible with the human voice, but with a similar scale of expediency; thus, slow systems (such as postal mail) are excluded from the field. The transmission media in telecommunication have evolved through numerous stages of technology, from beacons and other visual signals (such as smoke signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical cable and electromagnetic radiation, including light. Such transmission paths are often divided into communication channels, which afford the advantages of multiplexing multiple concurrent communication sessions. ''Telecommunication'' is often used in its plural form. Other examples of pre-modern long-distance communication included audio messages, such as coded d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simulation
A simulation is the imitation of the operation of a real-world process or system over time. Simulations require the use of models; the model represents the key characteristics or behaviors of the selected system or process, whereas the simulation represents the evolution of the model over time. Often, computers are used to execute the simulation. Simulation is used in many contexts, such as simulation of technology for performance tuning or optimizing, safety engineering, testing, training, education, and video games. Simulation is also used with scientific modelling of natural systems or human systems to gain insight into their functioning, as in economics. Simulation can be used to show the eventual real effects of alternative conditions and courses of action. Simulation is also used when the real system cannot be engaged, because it may not be accessible, or it may be dangerous or unacceptable to engage, or it is being designed but not yet built, or it may simply not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stochastic
Stochastic (, ) refers to the property of being well described by a random probability distribution. Although stochasticity and randomness are distinct in that the former refers to a modeling approach and the latter refers to phenomena themselves, these two terms are often used synonymously. Furthermore, in probability theory, the formal concept of a '' stochastic process'' is also referred to as a ''random process''. Stochasticity is used in many different fields, including the natural sciences such as biology, chemistry, ecology, neuroscience, and physics, as well as technology and engineering fields such as image processing, signal processing, information theory, computer science, cryptography, and telecommunications. It is also used in finance, due to seemingly random changes in financial markets as well as in medicine, linguistics, music, media, colour theory, botany, manufacturing, and geomorphology. Etymology The word ''stochastic'' in English was originally used as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications Forecasting
All telecommunications service providers perform forecasting calculations to assist them in planning their networks.Farr R.E., Telecommunications Traffic, Tariffs and Costs – An Introduction For Managers, Peter Peregrinus, 1988. Accurate forecasting helps operators to make key investment decisions relating to product development and introduction, advertising, pricing etc., well in advance of product launch, which helps to ensure that the company will make a profit on a new venture and that capital is invested wisely.Kennedy I. G., Forecasting, School of Electrical and Information Engineering, University of the Witwatersrand, 2003. Why is forecasting used? Forecasting can be conducted for many purposes, so it is important that the reason for performing the calculation is clearly defined and understood. Some common reasons for forecasting include: *Planning and Budgeting – Using forecast data can help network planners decide how much equipment to purchase and where to place it t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Performance
Network performance refers to measures of service quality of a network as seen by the customer. There are many different ways to measure the performance of a network, as each network is different in nature and design. Performance can also be modeled and simulated instead of measured; one example of this is using state transition diagrams to model queuing performance or to use a Network Simulator. Performance measures The following measures are often considered important: * Bandwidth commonly measured in bits/second is the maximum rate that information can be transferred * Throughput is the actual rate that information is transferred * Latency the delay between the sender and the receiver decoding it, this is mainly a function of the signals travel time, and processing time at any nodes the information traverses * Jitter variation in packet delay at the receiver of the information * Error rate the number of corrupted bits expressed as a percentage or fraction of the total sent Ban ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic Measurement (telecommunications)
Measurement of traffic within a network allows network managers and analysts to both make day-to-day decisions about operations and to plan for long-term developments.Penttinen A., ''Chapter 4 – Traffic Modelling and Measurements'', Lecture Notes: S-38.145 - Introduction to Teletraffic Theory, Helsinki University of Technology, Fall 1999.Kennedy I., ''Why Traffic Measurement? School of Electrical and Information Engineering, University of the Witwatersrand, 2003 Traffic Measurements are used in many fundamental activities such as: *Identification of traffic patterns and trends *Calculating the traffic intensity in a specific circuit or group *Monitoring the service *Dimensioning and managing the network *Calculating tariffs *Performing forecasting *Dimensioning and managing the SS7 network *Checking the performance of the common channel signalling network The following sections will answer some fundamental questions about Traffic Measurement, such as: What should be measured; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discrete Event Simulation
A discrete-event simulation (DES) models the operation of a system as a ( discrete) sequence of events in time. Each event occurs at a particular instant in time and marks a change of state in the system. Between consecutive events, no change in the system is assumed to occur; thus the simulation time can directly jump to the occurrence time of the next event, which is called next-event time progression. In addition to next-event time progression, there is also an alternative approach, called incremental time progression, where time is broken up into small time slices and the system state is updated according to the set of events/activities happening in the time slice. Because not every time slice has to be simulated, a next-event time simulation can typically run faster than a corresponding incremental time simulation. Both forms of DES contrast with continuous simulation in which the system state is changed continuously over time on the basis of a set of differential equations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random Number Generator
Random number generation is a process by which, often by means of a random number generator (RNG), a sequence of numbers or symbols that cannot be reasonably predicted better than by random chance is generated. This means that the particular outcome sequence will contain some patterns detectable in hindsight but unpredictable to foresight. True random number generators can be '' hardware random-number generators'' (HRNGS) that generate random numbers, wherein each generation is a function of the current value of a physical environment's attribute that is constantly changing in a manner that is practically impossible to model. This would be in contrast to so-called "random number generations" done by ''pseudorandom number generators'' (PRNGs) that generate numbers that only look random but are in fact pre-determined—these generations can be reproduced simply by knowing the state of the PRNG. Various applications of randomness have led to the development of several different metho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Channel Model
A communication channel refers either to a physical transmission medium such as a wire, or to a logical connection over a multiplexed medium such as a radio channel in telecommunications and computer networking. A channel is used for information transfer of, for example, a digital bit stream, from one or several ''senders'' to one or several '' receivers''. A channel has a certain capacity for transmitting information, often measured by its bandwidth in Hz or its data rate in bits per second. Communicating an information signal across distance requires some form of pathway or medium. These pathways, called communication channels, use two types of media: Transmission line (e.g. twisted-pair, coaxial, and fiber-optic cable) and broadcast (e.g. microwave, satellite, radio, and infrared). In information theory, a channel refers to a theoretical ''channel model'' with certain error characteristics. In this more general view, a storage device is also a communication ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Simulation
In computer network research, network simulation is a technique whereby a software program replicates the behavior of a real network. This is achieved by calculating the interactions between the different network entities such as routers, switches, nodes, access points, links, etc. Most simulators use discrete event simulation in which the modeling of systems in which state variables change at discrete points in time. The behavior of the network and the various applications and services it supports can then be observed in a test lab; various attributes of the environment can also be modified in a controlled manner to assess how the network/protocols would behave under different conditions. Network simulator A network simulator is a software program that can predict the performance of a computer network or a wireless communication network. Since communication networks have become too complex for traditional analytical methods to provide an accurate understanding of system behavior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Simulator
In computer network research, network simulation is a technique whereby a software program replicates the behavior of a real network. This is achieved by calculating the interactions between the different network entities such as routers, switches, nodes, access points, links, etc. Most simulators use discrete event simulation in which the modeling of systems in which state variables change at discrete points in time. The behavior of the network and the various applications and services it supports can then be observed in a test lab; various attributes of the environment can also be modified in a controlled manner to assess how the network/protocols would behave under different conditions. Network simulator A network simulator is a software program that can predict the performance of a computer network or a wireless communication network. Since communication networks have become too complex for traditional analytical methods to provide an accurate understanding of system behavior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobility Model
Mobility models characterize the movements of mobile users with respect to their location, velocity and direction over a period of time. These models play an vital role in the design of Mobile Ad Hoc Networks(MANET). Most of the times simulators play a significant role in testing the features of mobile ad hoc networks. Simulators like (NS, QualNet, etc.) allow the users to choose the mobility models as these models represent the movements of nodes or users. As the mobile nodes move in different directions, it becomes imperative to characterize their movements ''vis-à-vis'' to standard models. The mobility models proposed in literature have varying degrees of realism i.e. from random patterns to realistic patterns. Thus these models contribute significantly while testing the protocols for mobile ad hoc networks. Background and terminology The study of large and complex networks is possible by experimenting on a simulator rather than on analytical studies. The relatively new f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
