Question

Which of the following are characteristic features of SAS? (Select 3 answers)

A. Serial interface
B. Identifies devices on a SCSI chain via SCSI IDs and LUNs
C. Requires bus termination
D. Point-to-point connection
E. Parallel interface
F. Capability to attach multiple devices on a single bus via daisy chaining
G. Does not require bus termination

Answer 1

SAS is characterized by its serial interface, point-to-point connections, and the capability to attach multiple devices on a single SAS domain using expanders. Unlike parallel SCSI, it does not require bus termination and uses different methods for addressing devices.

Step-by-step explanation:

The characteristics of SAS (Serial Attached SCSI) include:

• Point-to-point connection: This means that each device is connected directly to the SAS controller, eliminating the need for bus sharing and thus avoiding contention for bandwidth.
• Serial interface: Unlike its predecessor, the parallel SCSI, SAS uses a serial interface to transfer data which provides higher speeds and scalability.
• Capability to attach multiple devices: SAS supports the connection of multiple devices in a daisy-chained or fan-out configuration through expanders, although it is not the same as the older SCSI bus.
• Here it is important to note that SAS does not require bus termination because it uses point-to-point connections, which inherently negates the need for termination. Moreover, SAS does not identify devices using SCSI IDs and LUNs in the same way as parallel SCSI; it uses worldwide names (WWNs) with SAS addresses.