Label switched routing in SAS expanders

The attaching of labels to an OPEN frame and applying label switched routing to SAS expanders is disclosed to eliminate the need for large routing tables in SAS networks. A label stack is inserted into the OPEN frame by the initiator, prior to the OPEN frame being transmitted. Each label contains the egress port for a SAS expander in the transmit path. Each SAS expander to be participating in the connection reads the labels to determine the egress port to connect to and through which data is to be sent. The SAS expander marks its label invalid or discards it and forwards the OPEN frame to the egress port where the next SAS expander will look for the first valid label. The process repeats until the OPEN frame reaches the edge device, at which time all labels are discarded and the OPEN frame is forwarded to the end device.