On the Usage of Virtual Paths, Virtual Channels, and Buffers in ATM Traffic Management
|Document type:||Conference Papers|
|Title:||On the Usage of Virtual Paths, Virtual Channels, and Buffers in ATM Traffic Management|
|Conference name:||12th Nordic Teletraffic Seminar (NTS12)|
|Publisher:||Technical research Centre of Finland|
|Organization:||Blekinge Institute of Technology|
|Department:||Dept. of Telecommunications and Mathematics (Institutionen för telekommunikation och matematik)
Dept. of Telecommunications and Mathematics S-371 79 Karlskrona
+46 455 780 00
|Abstract:||Traffic in ATM networks can be described by numerous parameters. On a per session
basis, one may use peak rate, average rate, sustainable rate, average burst duration,
average silence duration, and others. In a longer time scale, parameters like the average
and peakedness of connection request interarrival times, the average and variance of
session holding times, and so on are proposed.
Theoretically, users should provide the former parameters and network operators the
latter. In reality, however, few users can be expected to provide all sorts of statistical
information about their traffic in advance, and operators do not have enough experience
to prepare traffic forecasts for new services and applications. Moreover, even if the
information could be provided, the lack of simple yet valid traffic models for ATM
networks means that it is far from clear how such information should be used.
Realising that ATM networks, which are already being built, at least for the next
few years will have to operate under these uncertain conditions, we propose a robust and
forgiving network design and traffic management strategy. The idea is to use only little
information about offered traffics and then dynamically control resource allocations, so
as to provide acceptable quality of service combined with high utilisation.
The network design is based on the idea of keeping congestion at the edges of the net-
work, so that the operating areas of fast congestion control mechanisms are minimised.
Traffic variations are characterised by a model of six layers, each of which is assigned
a corresponding layer in a traffic management model. We define the functionalities of
each level in the latter modell and review possible implementations. In particular, we
report on an implementation of two of these layers and discuss in some detail how a
third one could be added.
|Subject:||Telecommunications\VP and VC Assignment and Routing|
|Note:||This article is written under the Project "VP and VC Assignment and Routing"|