Patent ID: 6480501
Filing Date: 2002-11-12
Classification: H04L

Abstract:
A method for routing a data cell in a self-routing switch fabric having a central switching structure and distributed Switch Core Access Layer (SCAL) elements that permit attachment of protocol adapters to the switch fabric; said method comprising the steps of:(a) in the receive part of each distributed SCAL: dividing the cell into a set of k logical units in order to permit the transport of the cell to the centralized switching structure through a set of k serialized links; introducing a set of additional bytes into one of said logical units, said bytes forming a bitmap field for carrying a bitmap which is used for performing routing and multicast operations on the cell; introducing in each logical unit a comma character in accordance with the 8B/10B coding process in every empty cell; (b) in the centralized switching structure: deserializing each coded logical unit in order to reconstitute the data cell; accessing a first routing storage in order to fill said bitmap field with a first bitmap value that will be used for controlling the routing process inside said switching structure; assessing a second routing storage at the output of the switching structure, in order to fill said bitmap field with a second bitmap value; dividing the data cell into a set of k logical units in order to prepare a serialization through k serial links and performing a similar 8B/10B coding process; (c) in the transmit part of the distributed SCAL receiving the serialized logical units: deserializing each coded logical unit in order to reconstitute the data cell; merging the coded logical unit by means of said comma character introduced into said switching structure; suppressing the said additional bytes in order to reconstitute the original cell that was received at the input point of the switch fabric.