Editing Teletraffic engineering (section)

{{Short description|Application of traffic engineering theory to telecommunications}}
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'''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 network]]s, 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 time much more predictable than the behaviour of individual parts of the system.