|
|
Teletraffic Engineering In Multi-service Networks This article is one of a group being considered for deletion in accordance with Wikipedia's deletion policy. Please see the policy discussion page of the votes for deletion list for details. This request is being discussed to form a consensus whether this is, or could be, an article appropriate for Wikipedia. If you feel deletion is not justified by Wikipedia deletion policy you may vote against its deletion. Please do not remove this notice or blank this article while the question is being considered. However, you are welcome to continue editing this article, especially if you can address the concerns of those who believe the article should be deleted. Should you do so, please remark on the policy discussion page regarding its improvement. This page examines in more detail the aspect of Teletraffic Engineering in Multi-Service (or Broadband) Networks. In particular, catering for multiple services for different types of traffic is examined, as well as congestion prevention and Congestion Control. What is Broadband Traffic? Traditional telephony traffic consisted of different data and voice streams combined (or multiplexed) into a single physical circuit, and subsequently, at the receiving end, the streams were demultiplexed (or separated), effectively breaking them out into their respective connections on the remote customer premise. Placing a multiplexer on both ends of the physical circuit in this manner provided a means to an end; it was considered economically more attractive to multiplex multiple data streams together into a single physical circuit than it was to purchase different individual circuits for each application. This economic principle still holds true today of Service. The predominant liability of this approach is that once multiplexed, it is impossible to manage each individual data stream. The introduction of ATM switching in the early 1990's provided an alternative method to traditional multiplexing, in which the basic concept (similar to its predecessor, frame relay) is that multiple Virtual Channels (VCs) or Virtual Paths (VPs) now could be used for multiple data streams. Many VCs can be delivered on a single VP, and many VPs can be delivered on a single physical circuit. This is very attractive from an economic, as well as a management, perspective. It allows each individual data stream to be managed and catered for independently, thereby allowing ATM to support virtually any type of traffic, such as voice, data, or video applications. Indeed, these different types of traffic have very different requirements in terms of bandwidth, latency and variation (see Teletraffic Engineering in ATM Networks for more information). This collection of different types of traffic is known as "Broadband traffic" (see also Broadband). The nature of broadband traffic is very different from traditional telephony traffic. Broadband traffic is "bursty", with multiple classes of traffic routed together. The statistical properties of broadband traffic are also different from traditional telephony traffic, and they are therefore also modelled differently (see Long-tail traffic). Teletraffic Engineering in broadband networks Broadband networks must provide different levels of Quality of Service to the different types of traffic that the network carries, while preventing congestion in the network. If congestion does occur in the network, Congestion Control must be applied to restore the network to a satisfactory operating level (see Congestion Control).
|
 |