Patent ID: 7444445

Claim:
A data storage domain, comprising: a serial attached SCSI (SAS) switch comprising one or more SAS interfaces, including a first SAS interface operable at least at a first data rate; a first SAS expander comprising one or more SAS interfaces; including a second SAS interface operable at least at the first data rate; a first smart cable attached between the first SAS interface and the second SAS interface and having a non-volatile memory storing persistent cable data including information relating to the signal degradation characteristics of the first smart cable; the first SAS expander further comprising a first processor programmed to: interrogate the first smart cable and any other smart cable attached between the first SAS expander and another SAS device in the data storage domain, the interrogation comprising a request for the cable persistent data of each attached smart cable; and capture in a table the cable persistent data of each attached smart cable; the SAS switch further comprising a second processor programmed to: direct that the one or more interfaces of the SAS switch and of the first SAS expander operate at the first data rate; collect the cable persistent data captured in the table; in response to the collected cable persistent data, determine a set of signal conditioning parameters for data being transmitted on each attached smart cable, the set of signal conditioning parameters including a maximum data rate; and transmit a command to the first processor to set the signal conditioning parameters for each attached smart cable in accordance with the set of determined signal conditioning parameters.