Method and apparatus for an automatic load balancing and back-up of a multi-users network

Abstract

The invention aims to implement the Load Balancing/Backup function in a Multi-Users environment and to allow a remote station to have an alternate route through another Token Ring DLC to backup. By directing the connection to another route, it postpones the connection from a remote station to a Token Ring user through a first selected Token Ring DLC for a predetermined delay. For that purpose, each Token Ring DLC stores parameters of the remote station that has an unsuccessful connection in its own Connection Cache Table. In this way, when a Test frame is received in each DLC, this latter checks in the Connection Cache Table before responding to the Test frame. The Test frame is ignored and no Test response is sent back to the remote station when the remote station is identified in the table so as to allow the remote station to detect an alternate route with a backup DLC if it exists. Each Token Ring DLC manages its own Connection Cache table which contains an entry, a source MAC address and a Source SAP and a counter indicating the number of unsuccessful attempted Test frames received from that remote station. If the counter reaches a value N, then the entry corresponding to the remote station is removed from the table. Thus, the next time a Test frame is received from this remote station, it is accepted and a response is sent from the DLC. It gives a new opportunity to the remote station to establish a connection to the user in case this latter would become available again.