Method and Apparatus for Transferring Data Between IP Network Devices and SCSI and Fibre Channel Devices Over an IP Network

Abstract

A method and apparatus for transferring data between IP devices (including, but not limited to, Gigabit Ethernet devices) and SCSI or Fibre Channel devices. The device interfaces may be either SCSI, Fibre Channel or IP interfaces such as Gigabit Ethernet. Data is switched between SCSI and IP, Fibre Channel and IP, or between SCSI and Fibre Channel. Data can also be switched from SCSI to SCSI, IP to IP and FC to FC. The port interfaces provide the conversion from the input frame format to an internal frame format, which can be routed within the apparatus. The amount of processing performed by each port interface is dependent on the interface type. The processing capabilities of the present invention permit rapid transfer of information packets between multiple interfaces at latency levels meeting the stringent requirements for storage protocols. The configuration control can be applied to each port on a switch and, in turn, each switch on the network, via an SNMP or Web-based interface, providing a flexible, programmable control for the apparatus.

1 . A network device configured to 
 intercept a frame having a buffer to buffer receive data field size and being transmitted to a destination on a network,    adjust the buffer to buffer receive data field size of the intercepted frame, and    route the modified frame to the destination on the network.    
     
     
         2 . A device according to  claim 1 , wherein the intercepted frame is a node login frame or a node login response frame.  
     
     
         3 . A device according to  claim 1 , wherein the buffer to buffer receive data field size is adjusted to allow Fibre Channel Protocol (FCP) data frames to fit into an IP packet that can be transmitted across the network without being fragmented.  
     
     
         4 . A device according to  claim 3 , wherein the network is an ethernet network.  
     
     
         5 . A device according to  claim 1 , wherein the device is configured to perform maximum transmission unit (MTU) discovery to determine a size that does not result in fragmentation of IP packets in the network, and the buffer to buffer receive data field size is adjusted to the size determined by MTU discovery.  
     
     
         6 . A method for limiting frame size, comprising: 
 intercepting a frame having a buffer to buffer receive data field size and being transmitted to a destination a network,    adjusting the buffer to buffer receive data field size of the intercepted frame, and    routing the modified frame to the destination on the network.    
     
     
         7 . A method according to  claim 6 , wherein the intercepted frame is a node login frame or a node login response frame.  
     
     
         8 . A method according to  claim 7 , wherein the buffer to buffer receive data field size is adjusted to allow Fibre Channel Protocol (FCP) data frames to fit into an IP packet that can be transmitted across the network without being fragmented.  
     
     
         9 . A method according to  claim 8 , wherein the network is an ethernet network.  
     
     
         10 . A method according to  claim 6 , further comprising performing maximum transmission unit (MTU) discovery to determine a size that does not result in fragmentation of IP packets in the network, and adjusting the buffer to buffer receive data field size to the size determined by MTU discovery.