What exactly is iSCSI? It is not NAS. It does not require SCSI disks. It is not a file sharing protocol like those used by Mac and Windows servers. It is not iFCP, which is a protocol used to connect FC SAN islands across long distances. Nor is it FCIP. iSCSI is extremely close to the Fibre Channel protocol. For those already familiar with Fibre Channel, iSCSI can be very loosely generalized as “Fibre Channel over Ethernet.”
By definition, iSCSI (Internet SCSI or “SCSI over IP”) is a storage networking standard that enables the transport of block I/O data over an IP network. iSCSI replaces SCSI’s direct-attached cabling architecture with a network fabric. Essentially, the protocol works by encapsulating SCSI commands into packets and transporting them via TCP/IP. In other words, your Ethernet network now has the potential to become… a SAN. And as a direct result of this ubiquitous, standardized Ethernet infrastructure come many interesting features and benefits that would otherwise be impossible.
Many would argue that simplicity is a key advantage of using iSCSI versus Fibre Channel to deploy a SAN. The reason – an iSCSI SAN doesn’t necessarily require the specialized hardware knowledge that is perceived to be a prerequisite with Fibre Channel. There is already an inherent level of familiarity with the various Ethernet networking components. Therefore, a company lacking a dedicated staff of storage network technicians should feel more adept at maintaining and troubleshooting an iSCSI SAN.
Although iSCSI can certainly be complementary to many other storage technologies, it is especially well-suited for a large portion of the “middle market.” That is, the mass of users who:
• need considerably more throughput than NAS or Client/Server can provide,
• desire the benefits of a SAN, and
• have determined Fibre Channel is somewhat excessive for their needs.
By definition, iSCSI (Internet SCSI or “SCSI over IP”) is a storage networking standard that enables the transport of block I/O data over an IP network. iSCSI replaces SCSI’s direct-attached cabling architecture with a network fabric. Essentially, the protocol works by encapsulating SCSI commands into packets and transporting them via TCP/IP. In other words, your Ethernet network now has the potential to become… a SAN. And as a direct result of this ubiquitous, standardized Ethernet infrastructure come many interesting features and benefits that would otherwise be impossible.
Many would argue that simplicity is a key advantage of using iSCSI versus Fibre Channel to deploy a SAN. The reason – an iSCSI SAN doesn’t necessarily require the specialized hardware knowledge that is perceived to be a prerequisite with Fibre Channel. There is already an inherent level of familiarity with the various Ethernet networking components. Therefore, a company lacking a dedicated staff of storage network technicians should feel more adept at maintaining and troubleshooting an iSCSI SAN.
Although iSCSI can certainly be complementary to many other storage technologies, it is especially well-suited for a large portion of the “middle market.” That is, the mass of users who:
• need considerably more throughput than NAS or Client/Server can provide,
• desire the benefits of a SAN, and
• have determined Fibre Channel is somewhat excessive for their needs.
An iSCSI SAN can be the solution in that it provides comparatively excellent throughput, delivers the benefits of consolidated storage, and requires less resources overall vs. Fibre Channel in terms of people or cost.
No comments:
Post a Comment