Apparatus and methods for a simplified, multi-client SAS port for management of other devices in an enhanced SAS device

A method operable in a Serial Attached Small Computer Systems Interface (SAS) expander to couple initiators with targets via the SAS protocol, the method comprising:

• establishing a SAS connection between a first of the initiators and a first of the targets through a single SAS port module of the expander via an arbiter, thus granting temporary exclusive access to the single SAS port;
• and
• via the arbiter of the SAS port module:
• processing a SAS Open Address Frame from the first target;
• determining which of a Serial Management Protocol (SMP) application interface, a Serial ATA Tunneled Protocol (STP) application interface, and a Serial SCSI Protocol (SSP) application interface will process subsequent SAS frames between the first initiator and the first target based on the SAS Open Address Frame;
• processing a subsequent SAS frame between the first initiator and the first target;
• and
• routing the subsequent SAS frame between the first initiator and the first target according to the determined application interface.

A non-transitory computer readable medium comprising instructions that, when executed by a processor within a Serial Attached Small Computer Systems Interface (SAS) expander, direct the processor to couple initiators with targets via the SAS protocol, the computer readable medium further comprising instructions that direct the processor to:

• establish a SAS connection between a first of the initiators and a first of the targets through a single SAS port module of the expander via an arbiter, thus granting temporary exclusive access to the single SAS port;
• and
• direct the arbiter of the SAS port module to:
• process a SAS Open Address Frame from the first target;
• determine which of a Serial Management Protocol (SMP) application interface, a Serial ATA Tunneled Protocol (STP) application interface, and a Serial SCSI Protocol (SSP) application interface will process subsequent SAS frames between the first initiator and the first target based on the SAS Open Address Frame;
• process a subsequent SAS frame between the first initiator and the first target;
• and
• route the subsequent SAS frame between the first initiator and the first target according to the determined application interface.