Serial Attached SCSI technologies and architectures, 4th edition

7
Figure 5: An internal topology for RAID systems using a SAS expander
External
Figure 6 shows a topology for connecting one port on a controller to an external storage enclosure.
This single controller port incorporates four lanes for a total maximum throughput of 2400 MB/s. The
storage enclosure contains an internal 36-port expander that supports cascading an additional
enclosure in a 1+1 configuration. Figure 6 also shows a topology for connecting both ports to the
enclosure. That doubles the bandwidth, which is important for some workloads.