Patent ID: 7385972
Filing Date: 2008-06-10
Classification: H04L,H04N

Abstract:
1. In a distributed system comprised of a plurality of nodes which are data consumers and data senders coupled by a switch and a plurality of Fibre Channel Arbitrated Loops, a process for establishing one or more concurrent data transfers between different pairs of nodes comprising the steps: (1) for each desired data transfer, sending to said switch from a source node a request to start a loop tenancy with a destination node, said request being in the form of a Fibre Channel Arbitrated Loop (hereafter FCAL) primitive and including a tag which identifies the destination node with which data is to be exchanged; (2) receiving said request and tag in a switching circuit coupled to the FCAL upon which said source node is resident and using said tag to determine from a table of nodes resident on said FCAL upon which said source node is resident if said destination node is resident thereon; (3) if said destination node is not resident on said FCAL upon which said source node is resident, using a control channel on a multiplexed bus having data transfer channels and control channels to circulate said request and tag to other switching circuits coupled each of said other FCALs; (4) in each said other switching circuit, using said tag to determine from a table of nodes resident on said FCAL to which said switching circuit is coupled if said destination node is resident on a local FCAL coupled to said switching circuit; (5) generating in the switching circuit coupled to the FCAL upon which said destination node is resident a grant message identifying the FCAL upon which said destination node is present by inclusion of the identification code of the switching circuit coupled to the FCAL on which said destination node is present in said grant message; (6) assiging one or more data transfer channels of said multiplexed bus to carry data of said desired data transfer so as to establish a data transfer path between said switching circuit coupled to said FCAL upon which said source node is present and the switching circuit coupled to said FCAL upon which said destination node is present to carry the data and FCAL primitives of the desired FCAL protocol data transfer; and (7) using said switching circuits coupled to said FCALs upon which said source and destination nodes are resident to couple an RRDY FCAL protocol primitive from said destination node to said source node after said data transfer path across said multiplexed bus has been established to trigger and control the flow of data, and placing the data of said desired data transfer in one or more of said data transfer channels of said multiplexed bus to carry out said data transfer.