Patent ID: 7377800

Claim:
A data storage system, comprising: (A) a first chassis having therein: a first pair of SAS expanders including a first SAS expander and a second SAS expander, each one having: a bidirectional front end point, a plurality of bidirectional backend points, and a keyed expansion point; (B) a second chassis having therein: a second pair of SAS expanders, including a third SAS expander and a fourth SAS expander each one of the pair of SAS expanders having a keyed bidirectional front end expansion point configured to receive only a correspondingly keyed backend datapath point and a keyed bidirectional backend expansion point configured to receive only a correspondingly keyed front end datapath point; (C) a first datapath having a keyed front end datapath point connected to the keyed expansion point of a first SAS expander and a keyed backend datapath point connected to the keyed front end expansion point of the third SAS expander; and (D) a second datapath having a keyed front end datapath point connected to the keyed expansion point of the second SAS expander and a keyed backend datapath point connected to the keyed front end expansion point of the fourth SAS expander.