| US 7,463,646 B2 | ||
| Method and system for fibre channel arbitrated loop acceleration | ||
| John M Fike, Austin, Tex. (US); and Patricia E Hareski, Austin, Tex. (US) | ||
| Assigned to Qlogic Corporation, Aliso Viejo, Calif. (US) | ||
| Filed on Jul. 12, 2004, as Appl. No. 10/889,267. | ||
| Claims priority of provisional application 60/492346, filed on Aug. 04, 2003. | ||
| Claims priority of provisional application 60/490747, filed on Jul. 29, 2003. | ||
| Claims priority of provisional application 60/487887, filed on Jul. 16, 2003. | ||
| Claims priority of provisional application 60/487876, filed on Jul. 16, 2003. | ||
| Claims priority of provisional application 60/487875, filed on Jul. 16, 2003. | ||
| Claims priority of provisional application 60/487873, filed on Jul. 16, 2003. | ||
| Claims priority of provisional application 60/487667, filed on Jul. 16, 2003. | ||
| Claims priority of provisional application 60/487665, filed on Jul. 16, 2003. | ||
| Prior Publication US 2005/0013318 A1, Jan. 20, 2005 | ||
| Int. Cl. H04L 12/42 (2006.01) | ||
| U.S. Cl. 370—462 [370/461] | 13 Claims |

| 1. A fibre channel switch element, comprising:
an acceleration device that (a) connects a plurality of fibre channel devices in an arbitrated loop; (b) monitors frames sent
by of the plurality of fibre channel devices during a loop initialization process to determine an arbitrated loop physical
address (AL_PA) value selected by each of the plurality of fibre channel devices; (c) creates an AL_PA table based on the
AL_PA values selected by each of the plurality of fibre channel devices, wherein the AL_PA table is stored in the acceleration
device and the AL_PA table is used for port selection; and (d) during an arbitration process only an arbitrating fibre channel
device and a host port for the acceleration device are connected to the arbitrated loop and the acceleration device sends
a benign primitive to non-arbitrating devices so that the non-arbitrating devices start the arbitration process when ports
of the non-arbitrating devices are ready for arbitration;
a global arbitration module that validates arbitration requests received from the plurality of fibre channel devices by using
the AL_PA table;
a controller module that operates in (i) a loop mode during which an isolated port receives data from an un-isolated port
but data from the isolated port is not sent to the arbitrated loop; (ii) a spray mode when there is no active traffic for
the arbitrated loop and data is sent from the host port to other ports; and (iii) a connection mode when there is traffic
for the arbitrated loop and an isolated port receives a primitive but is unable to send frames to the arbitrated loop; and
a state machine that uses a state of the arbitrated loop for changing fibre channel switch element states, instead of using
individual port states of the plurality of fibre channel device ports.
|