Erlang's loss formula and its use in designing packet switched networks.

摘要

Modern data communication systems usually consist of a number of routing nodes interconnected by communications links of various types. Because the links are single server elements, queuing in the routing nodes is necessary. However, a network design that eliminates queuing is possible. Erlang's Loss Formula is used as the basis of such a design. By multiplexing a large number of channels across the links between routing nodes, queuing can be eliminated while keeping packet loss acceptably low. Quality of service algorithms can also be eliminated. Because there is no queuing, the delay through the network is constant, meaning that compensation for variation in delay (fitter) is not necessary in real-time applications like voice-over-packet. The network can support packet switching functions in addition to emulating the circuit switched nature of the Public Switched Telephone Network. These characteristics make the network suitable for transport of computer-to-computer traffic (packet oriented) and real-time traffic (circuit oriented).