Differences between SAS and SATA

SAS and SATA are two specifications of the interface hard drive, both use serial technology, but there are relatively large differences in terms of compatibility, speed, price, and so on.

SAS, Serial Attached SCSI, or Serial Attached SCSI, is a new generation of SCSI technology that uses serial technology to obtain higher transfer speeds and improve internal space by shortening link lines, etc. SAS is a new interface developed after the parallel SCSI interface. This interface can improve the performance, availability and scalability of storage systems and provide compatibility with SATA hard drives.

SATA, Serial Advanced Technology Attachment, also known as serial hard disk, is the bus interface that connects the host bus adapter to the hard disk. Formalized in 2001 by the Serial ATA Committee, a group of major manufacturers including Intel, APT, Dell, IBM, Seagate, and Maxtor.

Different compatibility：

1. In the physical layer, SAS interface and SATA interface are fully compatible, SATA hard disk can be directly used in SAS environment, in terms of interface standard, SATA is a substandard of SAS, so SAS controller can directly control SATA hard disk, but SAS cannot be directly used in SATA environment, because SATA controller does not have control over SAS hard disk control;

2. At the protocol layer, SAS consists of three types of protocols, which are used for data transfer according to the different devices connected. The Serial SCSI Protocol (SSP) is used to transmit SCSI commands; the SCSI Management Protocol (SMP) is used for maintenance and management of the connected devices; and the SATA Channel Protocol (STP) is used for data transfer between SAS and SATA. Therefore, with the cooperation of these three protocols, SAS can be seamlessly integrated with SATA and some SCSI devices.

Different speed：

1. The speed of SAS is 12Gbps/S; 

2. The speed of SATA is 6Gbps/S.

Different price：

The price of SAS is more expensive than SATA.

There are other differences between SAS and SATA. Dongguan Aiqun Industrial Co., Ltd.is a company specializing in the development and production of high-speed cables. Through continuous innovation and optimization, we have produced a large number of SAS and SATA related products, which have been widely recognized by our customers.