SAS2

SAS2, also known as Serial Attached SCSI 2, is a high-speed data transfer interface standard. It is an evolution of the Serial Attached SCSI (SAS) standard, designed to offer increased performance and capabilities for storage devices. SAS2 was developed by the T10 technical committee of the International Committee for Information Technology Standards (INCITS).

The primary advancement in SAS2 over its predecessor was its doubled signaling rate. While SAS offered speeds up to 3 Gbit/s per lane, SAS2 increased this to 6 Gbit/s per lane. This enhancement allows for significantly faster data transfer between host systems and storage devices like hard disk drives and solid-state drives. This increased bandwidth is crucial for demanding applications such as enterprise storage, high-performance computing, and data-intensive workloads.

SAS2 maintains backward compatibility with earlier SAS generations, meaning SAS2 controllers can communicate with SAS1 drives and vice versa, although operating at the lower common speed. It also retains the complex topology of SAS, supporting point-to-point connections, and allowing for multiple expanders to create large storage area networks. This scalability makes SAS2 a robust solution for environments requiring extensive storage capacity and high availability. The interface also supports features like dual-porting for redundancy and failover, ensuring continuous data access.