There are several advantages of SAS in terms of performance, scalability, configuration, reliability and flexibility. The details of the advantages are explained as:
1. Performance- It delivers microprocessor speed, advance application and provides many point-to-point connections that allow fault-tolerant designs. The devices can transfer data in both directions simultaneously efficiently doubling the usable bandwidth of the link rate. The wide ports allow for multiple serial links while narrow ports support single links. SAS allows data handling features such as out-of-order queuing and head-of-queue which help system to rearrange and prioritize commands within the interface.
2. Flexibility- The main benefit of SAS is that it allows the use of both SATA and SAS drives in a system. SAS-SATA compatibility helps in designing hybrid storage systems using cabling and connectors. The SAS backplane connectors receive both SATA and SAS devices while SATA backplane connect only to SATA devices. Therefore, the backplane with SAS connectors offer more design flexibility.
3. Scalability- Parallel buses have imperfect scalability as they share connection paths and add more buses with multiple initiator, do slightly to expand the limited sharing ability. SAS uses expander hardware as a switch to make simpler configuration of huge external storage systems. These are easily scaled with minimum latency while preserving bandwidth for enlarged workloads. The expander hardware makes extremely flexible storage topologies.
4. Reliability and availability- Multiple initiator are used in project computing to offer disk drive access to multiple hosts, host bus adapters or both, which make sure nonstop data access if one fails. But, using multiple initiator in parallel technology configurations put down single points of failure, which can block access to a device. By using SAS, dual-ported devices are used to make high availability systems with no single points of failure. One can also boost up the fault tolerance with SAS by connecting multiple devices to multiple initiators. This sustains simultaneous operation to several devices. Commands are sent down on one link and data returned on another link in a separate connection to increase more fault tolerance.
There are different SAS accessories like cables, adapters and many more. The different types of mini SAS adapters are explained below:
1. Port SFF 8087 to 8088 Adapter- All work on both the sides i.e. host and device side. It is essential to mention the need of a bracket, slot-L bracket or low-profile L-bracket in the special Instructions field during checkout. To convert a mini SAS to SATA, it is necessary to make use of correct cable for the application.
2. 2 Port SFF 8087 to 8088 Adapter- Dual-port external 8088 to internal 8087 adapter work on both device and host side.
3. 4 Port SFF 8087 to 8088 Adapter- Quad-port external 8088 to internal 8087 L-Bracket adapter supports Utmost 16 hard drives.
4. SFF 8087 female to Female Adapter/Coupler- It is an inline coupler to connect two SFF 8087 cables together.
5. 4 Internal 7 Pin SAS/SATA to External SAS adapter bracket- It is perfect for raising existing areas to SAS or SATA. It supports SATA hard drives 4 SAS.
6. 4 Port SFF 8088 to 7 Pin SAS PCI Adapter- The input and output adapter to 4 internal SAS bus connections with 8088 external cross over pin out. It is attached to a PCI bracket.