SAS allows a higher transfer speed (3, 6 or 12Gbit/s) than most parallel SCSI standards. SAS achieves these speeds on each initiator-target connection, hence getting higher throughput, whereas parallel SCSI shares the speed across the entire multidrop bus. SAS controllers may connect to SATA devices, either directly connected using native SATA protocol or through SAS expanders using Serial ATA Tunneling Protocol (STP).

Mini Multilane 4/8X 12 Gb/s Unshielded Connector (HD12un), Rev 3.5". Archived from the original on June 6, 2021. I am still learning about SAS but was told to build a system from a potential employer utilizing these connections. However, I am just not sure I understand the concept on how the system will treat the SATA connections which are going into the SAS port via this cable. Shielded High Speed Serial Multilane Copper Connector, Rev 3.3". Archived from the original on June 6, 2021. Because of its higher signaling voltages, SAS can use cables up to 10m (33ft) long, whereas SATA has a cable-length limit of 1m (3.3ft) or 2m (6.6ft) for eSATA. [11]Mini Multilane 4/8X Unshielded Connector (HDun), Rev 3.5". Archived from the original on June 6, 2021. servethehome (2011-01-31). "SAS/ SATA SFF-8087, 8088, 8470, 8482, 8484 Connectors Guide". ServeTheHome . Retrieved 2021-01-12. SFF-8088 cables are fairly expensive, but are a great way to have a high speed connection directly from a RAID controller to a SAS expander chassis. If one does not have a RAID card with a SFF-8088 connector, one can utilize a SFF-8087 to SFF-8088 converter to achieve a similar result. SFF-8470 External four channel connector – Infiniband Type (data only) SFF-8470 Infiniband CX4 Connectors I was using Infiniband for an Ethernet over Infiniband test in 2010. One thing is certain about these cables, CX4 style cables are expensive! On the other hand, the SFF-8470 connectors do tend to be made from very solid metal housings that clip into place. This easily beats eSATA in terms of securing cables from external forces that may have the tendency to dislodge eSATA cables. SFF-8482 Internal single channel connector (data and power) SFF-8482 Connectors The SFF-8087 is compliant with the latest 6Gb/s Mini-SAS 2.0 spec, and supports 6Gb/s data transfer protocol

Infiniband, what can it not do? For those that do not know Infiniband, it is more or less a high-performance computing fabric developed to achieve high bandwidth and low latencies. CX4 cabling is used with a SFF-8470 connector to provide a high-performance SAS interconnect. Most newer generation SAS cards have since adopted the SFF-8088 connector, but some legacy products can still be found with the SFF-8470 connector. Interestingly enough, the CX4/ SFF-8470 connectors are also used on cards that provide high-speed data transmission between servers, making Infiniband not an exclusively storage related connector. SAS allows up to 65,535 devices through the use of expanders, while Parallel SCSI has a limit of 8 or 16 devices on a single channel. The components known as Serial Attached SCSI Expanders (SAS Expanders) facilitate communication between large numbers of SAS devices. Expanders contain two or more external expander-ports. Each expander device contains at least one SAS Management Protocol target port for management and may contain SAS devices itself. For example, an expander may include a Serial SCSI Protocol target port for access to a peripheral device. An expander is not necessary to interface a SAS initiator and target but allows a single initiator to communicate with more SAS/SATA targets. A useful analogy: one can regard an expander as akin to a network switch in a network, which connects multiple systems using a single switch port. Establish and tear down tunneled connections between SAS initiators and SATA targets connected to SAS expandersAn initiator may connect directly to a target via one or more PHYs (such a connection is called a port whether it uses one or more PHYs, although the term wide port is sometimes used for a multi-PHY connection). Mini Multilane 4/8X 12 Gb/s Shielded Cage/Connector (HD12sh), Rev 3.5". Archived from the original on November 12, 2020.