In computing, a protocol is a set of commands and rules that enables two entities to communicate
with each other. In storage, there are various protocols that allow a server and a storage
device to connect and exchange data. Usually each protocol also provides its own
physical interface specifications. This affects the type of connectors and the cables that
are used to connect the storage drive to a server.
There various protocols for connecting a storage drive to a server. Some common protocols are :
Serial Advanced Technology Attachment or SATA,
Small Computer System Interface or
SCSI,
Serial Attached SCSI or SAS,
Nearline SAS or NL-SAS, and
Fibre Channel or FC.
On the storage device, these protocols are implemented on the drive controller.
On the server, these protocols are either implemented on the motherboard or
by using adapters that plug into the motherboard. These protocols are applicable
to both DAS and networked storage environments.
Sata
The SATA interface is commonly found in consumer desktops and laptops. In enterprises, they provide cheap, low performance, and high capacity storage. SATA drives are typically used
for data backups and archiving.
SCSI
The SCSI interface is popular for enterprise storage. SCSI drives provide parallel transmission
and are used for high-performance, mission-critical workloads.
SAS is the serial point-to-point variant of the SCSI protocol, and it is also used in
high-end computing.
Nearline SAS or NL-SAS
Is a hybrid of SAS and SATA interfaces. Theses drives have a SAS interface and support
the SAS protocol. But in the back end they use SATA drives. They cost lesser than
SAS drives, and provide the benefit of the SCSI command set. At the same time they
offer the large capacities of SATA drives.
The Fibre Channel or FC protocol
Is also based on the SCSI protocol. FC is a widely used standard for networked storage.
It provides very high throughputs, with the latest standard supporting transfer
rates of up to 16 gigabits per second. When it comes to disk drives, there is always
a connection between the RPM and the capacity of a disk drive. Usually, drives with higher
RPM have lower capacity. Conversely, drives with lower RPM have a higher capacity.
Therefore high speed drives usually implement the protocols that provide better performance.
For example, 10K and 15K drives are usually SAS and FC drives.
On the other hand, 5.4K and 7.2K drives are usually SATA drives.
with each other. In storage, there are various protocols that allow a server and a storage
device to connect and exchange data. Usually each protocol also provides its own
physical interface specifications. This affects the type of connectors and the cables that
are used to connect the storage drive to a server.
There various protocols for connecting a storage drive to a server. Some common protocols are :
Serial Advanced Technology Attachment or SATA,
Small Computer System Interface or
SCSI,
Serial Attached SCSI or SAS,
Nearline SAS or NL-SAS, and
Fibre Channel or FC.
On the storage device, these protocols are implemented on the drive controller.
On the server, these protocols are either implemented on the motherboard or
by using adapters that plug into the motherboard. These protocols are applicable
to both DAS and networked storage environments.
Sata
The SATA interface is commonly found in consumer desktops and laptops. In enterprises, they provide cheap, low performance, and high capacity storage. SATA drives are typically used
for data backups and archiving.
SCSI
The SCSI interface is popular for enterprise storage. SCSI drives provide parallel transmission
and are used for high-performance, mission-critical workloads.
SAS is the serial point-to-point variant of the SCSI protocol, and it is also used in
high-end computing.
Nearline SAS or NL-SAS
Is a hybrid of SAS and SATA interfaces. Theses drives have a SAS interface and support
the SAS protocol. But in the back end they use SATA drives. They cost lesser than
SAS drives, and provide the benefit of the SCSI command set. At the same time they
offer the large capacities of SATA drives.
The Fibre Channel or FC protocol
Is also based on the SCSI protocol. FC is a widely used standard for networked storage.
It provides very high throughputs, with the latest standard supporting transfer
rates of up to 16 gigabits per second. When it comes to disk drives, there is always
a connection between the RPM and the capacity of a disk drive. Usually, drives with higher
RPM have lower capacity. Conversely, drives with lower RPM have a higher capacity.
Therefore high speed drives usually implement the protocols that provide better performance.
For example, 10K and 15K drives are usually SAS and FC drives.
On the other hand, 5.4K and 7.2K drives are usually SATA drives.
Nenhum comentário:
Postar um comentário