Interface Switch for use with Fibre Channel Fabrics in Storage Area Networks

Abstract

An interface switch which presents itself as switch to an enterprise fabric formed of the devices from the same manufacturer as the interface switch and that of a host or node to an enterprise fabric from a different manufacturer. This allows each enterprise fabric to remain in a higher performance operating mode. The multiplexing of multiple streams of traffic between the N_ports on the first enterprise fabric and the second enterprise fabric is accomplished by N_port Virtualization. The interface switch can be connected to multiple enterprise fabrics. All control traffic address mappings between virtual and physical addresses may be mediated and translated by the CPU of the interface switch and address mappings for data traffic performed at wire speed. Since the interface switch may preferably be a single conduit between the enterprise fabrics, it is also a good point to enforce perimeter defenses against attacks.

What is claimed is: 
     
         1 . A data switching device for connecting first and second fabrics, each fabric having at least one node connected, the device comprising:
 a plurality of external inter-switch ports for directly connecting to the first fabric;   an external node port for directly connecting to the second fabric;   a switch coupled to said plurality of inter-switch ports and said node port and interconnecting said ports;   wherein said node port operates as a virtual node port; and   wherein said plurality of external inter-switch ports form a portion of the first fabric when connected.   
     
     
         2 . The device of  claim 1 , wherein there is one virtual node address for each of the nodes connected to the first fabric. 
     
     
         3 . The device of  claim 1 , wherein said switch performs address translations between said plurality of external inter-switch ports and said external node port. 
     
     
         4 . A network comprising:
 a first fabric with at least one node connected;   a second fabric; and   a data switching device directly connected to said first and second fabrics, said device including:
 a plurality of external inter-switch ports directly connected to said first fabric and forming a portion of said first fabric; 
 a virtual external node port directly connected to said second fabric; and 
 a switch coupled to said plurality of external inter-switch ports and said external node port for interconnecting said ports. 
   
     
     
         5 . The network of  claim 4 , wherein there is one virtual node address for each of the nodes connected to the first fabric. 
     
     
         6 . The network of  claim 4 , wherein said switch performs address translations between said plurality of external inter-switch ports and said external node port. 
     
     
         7 . A network comprising:
 first and second fabrics;   a series of nodes, each having two ports, one port of each node connected to one of said first and second fabrics;   a third fabric; and   two data switching devices, each directly connected to said third fabric, with one device directly connected to said first fabric and one device directly connected to said second fabric, each said device including:
 a plurality of external inter-switch ports directly connected to said respective first or second fabric and forming a portion of that fabric; 
 a virtual external node port directly connected to said third fabric; and 
 a switch coupled to said plurality of external inter-switch ports and said external node port for interconnecting said ports. 
   
     
     
         8 . The network of  claim 7 , wherein there is one virtual node address for each of the nodes connected to the first or second fabric. 
     
     
         9 . The network of  claim 7 , wherein said switch performs address translations between said plurality of external inter-switch ports and said external node port. 
     
     
         10 . A network comprising:
 first and second fabrics;   a series of nodes, each having two ports, one port of each node connected to one of said first and second fabrics;   third and fourth fabrics; and   two data switching devices, one directly connected to said first, third and fourth fabrics, and one directly connected to said second, third and fourth fabrics, each said device including:
 a plurality of external inter-switch ports directly connected to said respective first or second fabric and forming a portion of that fabric; 
 two virtual external node ports, one directly connected to each of said third and fourth fabrics; and 
 a switch coupled to said plurality of external inter-switch ports and said two external node ports for interconnecting said ports. 
   
     
     
         11 . The network of  claim 10 , wherein there is one virtual node address for each of the nodes connected to the first or second fabric. 
     
     
         12 . The network of  claim 10 , wherein said switch performs address translations between said plurality of external inter-switch ports and said external node ports. 
     
     
         13 . A network comprising:
 first and second fabrics;   a series of nodes, each having two ports, one port of each node connected to one of said first and second fabrics;   third and fourth fabrics; and   two data switching devices, one directly connected to said first and third fabrics and one directly connected to said second and fourth fabrics, each said device including:
 a plurality of external inter-switch ports for directly connecting to said respective first or second fabric and forming a portion of that fabric; 
 two virtual external node ports for directly connecting to one of said third or fourth fabrics; and 
 a switch coupled to said plurality of external inter-switch ports and said two external node ports for interconnecting said ports. 
   
     
     
         14 . The network of  claim 13 , wherein there is one virtual node address for each of the nodes connected to the first or second fabric. 
     
     
         15 . The network of  claim 13 , wherein said switch performs address translations between said plurality of external inter-switch ports and said external node ports. 
     
     
         16 . A method for routing between first and second fabrics using a data switching device, the method comprising:
 providing a plurality of external inter-switch ports on the device for directly connecting to the first fabric and forming a portion of the first fabric when connected;   providing a virtual external node port on the device for directly connecting to the second fabric; and   interconnecting said plurality of external inter-switch ports and said external node port.   
     
     
         17 . The method of  claim 16 , further comprising assigning one virtual node address for each of the nodes connected to the first fabric. 
     
     
         18 . The method of  claim 16 , further comprising:
 performing address translations between said plurality of external inter-switch ports and said external node port.   
     
     
         19 . A data switching device comprising:
 a plurality of external inter-switch ports for directly connecting to a first fabric having at least one node connected;   an external node port for directly connecting to a second fabric having at least one node connected;   a switch coupled to said plurality of external inter-switch ports and said external node port and interconnecting said ports;   wherein said external node port operates as a virtual node port; and   wherein said plurality of external inter-switch ports form a portion of the first fabric when connected.   
     
     
         20 . The device of  claim 19 , wherein there is one virtual node address for each of the nodes connected to the first fabric. 
     
     
         21 . The device of  claim 19 , wherein said switch performs address translations between said plurality of external inter-switch ports and said external node port.