Local area network embedded in the communication switch core
AssigneeNorthern Telecom Limited
InventorsEric J. Dormer, Ernst A. Munter
Life of this patent
Estimating the term…
Abstract
Local area networks which take advantage of the star configuration of the switched telecommunication networks are disclosed. The local area networks of the present invention use a small part of the central memory of the switch core and employ either centralized or distributed logical bus collision control mechanisms to provide inherent broadcast capability.
Claims14
In a switched communication network containing a common switch core and nodes among which data are switched in framed cells by way of a core memory of said common switch core, each frame being composed of an administration cell and zero or more data cells, a local area network for transmitting LAN data cells among said nodes by using said administration cell, comprising:
- said common switch core having at least first and second LAN data memory locations in said core memory, said first and second LAN data memory locations alternately functioning as a collection location for storing a LAN data cell to be broadcast and as a broadcast location for holding a LAN data cell that is being broadcast in each successive frame time;
- and
- said nodes connected to said common switch core and arranged in a physical star fashion relative to said common switch core in a predetermined logical order, so that each node reads said LAN data cell held in said broadcast location and writes its own LAN data cell in said collection location in each successive frame time in said logical order.
In a switched communication network containing a common switch core and nodes connected to said common switch core in a star fashion among which nodes data are switched in framed cells by way of a core memory of said common switch core, each frame composed of an administration cell and zero or more data cells, a method of switching a LAN data cell using said administration cell among said nodes in a local area network formed in said switched communication network by connecting said nodes in a predetermined logical order, comprising steps of:
- each node reading a LAN data cell stored in a first LAN data memory location of said core memory and sending to said common switch core either a competing LAN data cell to be collected in a second LAN data memory location thereof or an indication of no competition, during each successive frame time;
- reversing the role of said first and second LAN data memory locations in each successive frame time;
- and
- repeating said frame times until no node has a competing LAN data cell to send to said common switch core.
Dependencies are inferred from the claim text.