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Teletraffic
Teletraffic engineering, or telecommunications traffic engineering is the application of traffic engineering (transportation), transportation traffic engineering theory to telecommunications. Teletraffic engineers use their knowledge of statistics including queuing theory, the nature of traffic, their practical models, their measurements and Network traffic simulation, simulations to make predictions and to plan telecommunication networks such as a telephone network or the Internet. These tools and knowledge help provide reliable service at lower cost. The field was created by the work of A. K. Erlang for circuit-switched networks but is applicable to packet-switched networks, as they both exhibit Markov property, Markovian properties, and can hence be modeled by e.g. a Poisson process, Poisson arrival process. The observation in traffic engineering is that in large systems the law of large numbers can be used to make the aggregate properties of a system over a long period of tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic Contract
If a network service (or application) wishes to use a broadband network (an ATM network in particular) to transport a particular kind of traffic, it must first inform the network about what kind of traffic is to be transported, and the performance requirements of that traffic.Hiroshi Saito, Teletraffic Technologies in ATM Networks, Artech House, 1993. . The application presents this information to the network in the form of a traffic contract. The Traffic descriptor When a connection is requested by an application, the application indicates to the network:Ferguson P., Huston G., Quality of Service: Delivering QoS on the Internet and in Corporate Networks, John Wiley & Sons, Inc., 1998. . *The Type of Service required. *The Traffic Parameters of each data flow in both directions. *The quality of service (QoS) Parameters requested in each direction. These parameters form the ''traffic descriptor'' for the connection. Type of Service Currently, five ATM Forum-defined servi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Traffic
This article discusses the mobile cellular network aspect of teletraffic measurements. Mobile radio networks have traffic issues that do not arise in connection with the fixed line PSTN. Important aspects of cellular traffic include: quality of service targets, traffic capacity and cell size, spectral efficiency and sectorization, traffic capacity versus coverage, and channel holding time analysis. Teletraffic engineering in telecommunications network planning ensures that network costs are minimised without compromising the quality of service (QoS) delivered to the user of the network. This field of engineering is based on probability theory and can be used to analyse mobile radio networks, as well as other telecommunications networks. A mobile handset which is moving in a cell will record a signal strength that varies. Signal strength is subject to slow fading, fast fading and interference from other signals, resulting in degradation of the carrier-to-interference ratio (C/I) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long-tail Traffic
A long-tailed or heavy-tailed distribution is one that assigns relatively high probabilities to regions far from the mean or median. A more formal mathematical definition is given below. In the context of teletraffic engineering a number of quantities of interest have been shown to have a long-tailed distribution. For example, if we consider the sizes of files transferred from a web server, then, to a good degree of accuracy, the distribution is heavy-tailed, that is, there are a large number of small files transferred but, crucially, the number of very large files transferred remains a major component of the volume downloaded. Many processes are technically long-range dependent but not self-similar. The differences between these two phenomena are subtle. Heavy-tailed refers to a probability distribution, and long-range dependent refers to a property of a time series and so these should be used with care and a distinction should be made. The terms are distinct although superpositio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of transmission may be divided into communication channels for multiplexing, allowing for a single medium to transmit several concurrent Session (computer science), communication sessions. Long-distance technologies invented during the 20th and 21st centuries generally use electric power, and include the electrical telegraph, telegraph, telephone, television, and radio. Early telecommunication networks used metal wires as the medium for transmitting signals. These networks were used for telegraphy and telephony for many decades. In the first decade of the 20th century, a revolution in wireless communication began with breakthroughs including those made in radio communications by Guglielmo Marconi, who won the 1909 Nobel Prize in Physics. Othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queuing Theory
Queueing theory is the mathematical study of waiting lines, or queues. A queueing model is constructed so that queue lengths and waiting time can be predicted. Queueing theory is generally considered a branch of operations research because the results are often used when making business decisions about the resources needed to provide a service. Queueing theory has its origins in research by Agner Krarup Erlang, who created models to describe the system of incoming calls at the Copenhagen Telephone Exchange Company. These ideas were seminal to the field of teletraffic engineering and have since seen applications in telecommunications, traffic engineering, computing, project management, and particularly industrial engineering, where they are applied in the design of factories, shops, offices, and hospitals. Spelling The spelling "queueing" over "queuing" is typically encountered in the academic research field. In fact, one of the flagship journals of the field is '' Queuein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Queueing Theory
Queueing theory is the mathematical study of waiting lines, or queues. A queueing model is constructed so that queue lengths and waiting time can be predicted. Queueing theory is generally considered a branch of operations research because the results are often used when making business decisions about the resources needed to provide a service. Queueing theory has its origins in research by Agner Krarup Erlang, who created models to describe the system of incoming calls at the Copenhagen Telephone Exchange Company. These ideas were seminal to the field of teletraffic engineering and have since seen applications in telecommunications, traffic engineering, computing, project management, and particularly industrial engineering, where they are applied in the design of factories, shops, offices, and hospitals. Spelling The spelling "queueing" over "queuing" is typically encountered in the academic research field. In fact, one of the flagship journals of the field is '' Queue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic Shaping
Traffic shaping is a bandwidth management technique used on computer networks which delays some or all datagrams to bring them into compliance with a desired ''traffic profile''. Traffic shaping is used to optimize or guarantee performance, improve latency, or increase usable bandwidth for some kinds of packets by delaying other kinds. It is often confused with traffic policing, the distinct but related practice of packet dropping and packet marking. The most common type of traffic shaping is application-based traffic shaping. In application-based traffic shaping, fingerprinting tools are first used to identify applications of interest, which are then subject to shaping policies. Some controversial cases of application-based traffic shaping include bandwidth throttling of peer-to-peer file sharing traffic. Many application protocols use encryption to circumvent application-based traffic shaping. Another type of traffic shaping is route-based traffic shaping. Route-based traf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic Mix
Traffic mix is a traffic model in telecommunication engineering and teletraffic theory. Definitions A traffic mix is a modelisation of user behaviour. In telecommunications, user behaviour activities may be described by a number of systems, ranging from simple to complex. For example, for plain old telephone service (POTS), a sequence of connection requests to an exchange can be modelled by fitting negative exponential distributions to the average time between requests and the average duration of a connection. This in turn can be used to work out the utilisation of the line for the purposes of network planning and dimensioning. Objectives Traffic mix has two goals: * Network links dimensioning * Network equipment dimensioning Both these functions are extremely important to network operators. If insufficient capability is deployed at a node (for example, if a backbone router has 1 gigabit/sec of switching capacity and more than this is offered) then the risk of equipment failure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Busy Hour Call Attempts
In telecommunications, busy-hour call attempts (BHCA) is a teletraffic engineering measurement used to evaluate and plan capacity for telephone networks. BHCA is the number of telephone calls attempted at the sliding 60-minute period during which occurs the maximum total traffic load in a given 24-hour period (BHCA), and the higher the BHCA, the higher the stress on the network processors. BHCA is not to be confused with busy hour call completion (BHCC) which measures the throughput capacity of the network. If a bottleneck in the network exists with a capacity lower than the estimated BHCA, then congestion will occur resulting in many failed calls and customer dissatisfaction. BHCA is usually used when planning telephone switching capacities and frequently goes side by side with the Erlang unit capacity calculation. As an example, a telephone exchange with a capacity of one million BHCA is estimated to handle 250,000 subscribers. The overall calculation is more complex however, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of transmission may be divided into communication channels for multiplexing, allowing for a single medium to transmit several concurrent Session (computer science), communication sessions. Long-distance technologies invented during the 20th and 21st centuries generally use electric power, and include the electrical telegraph, telegraph, telephone, television, and radio. Early telecommunication networks used metal wires as the medium for transmitting signals. These networks were used for telegraphy and telephony for many decades. In the first decade of the 20th century, a revolution in wireless communication began with breakthroughs including those made in radio communications by Guglielmo Marconi, who won the 1909 Nobel Prize in Physics. Othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
