What is iSCSI Storage Solution Is it one of the Top Storage Technologies

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If you aspire to be a professional in Storage IT company its a MUST to know FC & iSCSI. There was a previous post about FC & below is a brief on iSCSI .
As per Wikipedia's definition Internet SCSI (iSCSI) is a network protocol standard, officially ratified on 2003-02-11 by the Internet Engineering Task Force, that allows the use of the SCSI protocol over TCP/IP networks. iSCSI is a transport layer protocol in the SCSI-3 specifications framework. Other protocols in the transport layer include SCSI Parallel Interface and Fibre Channel.
The iSCSI (pronounced eye-skuzzy) protocol uses TCP/IP for its data transfer. Unlike other network storage protocols, such as Fibre Channel (which is the foundation of most SANs), it requires only the simple and ubiquitous Ethernet interface (or any other TCP/IP-capable network) to operate. This enables low-cost centralization of storage without all of the usual expense and incompatibility normally associated with Fibre Channel storage area networks.

Acceptance of iSCSI in corporate production environments has accelerated now that Gigabit Ethernet is common. Building iSCSI-based Storage Area Networks (SAN) has become a less costly but worthy alternative to creating Fibre Channel-based SANs.

iSCSI terminology and how iSCSI can be used by an OS

An iSCSI initiator, in client/server terminology, is akin to a client device that connects to some service offered by the server (in this case an iSCSI target). An iSCSI target is akin to a server, in that it provides block level access to its storage media (usually a hard drive, but can be other types of SCSI devices if the iSCSI target software supports them.) The primary difference between a regular client/server system and an iSCSI initiator/target system is that while many clients can be simultaneously served by a single server (many-to-one), only one iSCSI initiator can talk to a given iSCSI target at a time (one-to-one).

iSCSI can be used to give an OS block-level access to a remote device (one attached to another computer likely on the same LAN). Depending on the types of devices supported by the iSCSI target, this block-level access can be used to build RAID volumes using remote disks, or to connect and use remote DVD/CD-writers and scanners, or to simply access additional storage space. iSCSI devices are not shared by iSCSI amongst multiple computers at the same time; instead the OS in control of the iSCSI device is responsible for controlling remote access to the device. The initiator and the OS that it is running on will determine how the iSCSI device appears, and whether it is a /dev entry or gets a drive letter or something else.
Source : Weblinkhttp://en.wikipedia.org/wiki/Iscsi


ESG reports that it has identified 2500 iSCSI SAN deployments, and expects deployments to increase substantially in 2005. According to another ESG study of 130 SMB end users, 17% have already deployed an iSCSI SAN, and another 42% are planning to deploy iSCSI SANs by mid 2006. Spectra Logic’s interactions with customers support ESG’s expectations, given the increasing rate of Spectra Logic’s iSCSI products sales, the increasing support of iSCSI drivers/initiators by major operating systems, and the major vendor commitments to the technology.

Microsoft continues to be a major force behind iSCSI, pushing to make iSCSI SAN deployment even easier and even more “risk-free” to the masses. Considering that most of the growth within the storage market will come from small to medium businesses–environments heavily dominated by Windows and Linux–other major storage vendors are certainly enticed to work with MS to make “iSCSI SANs for the masses” a reality. Economics of scale make their decision and direction an easy one, further eased in that iSCSI is already supported in most operating systems.

Source :Weblink from spectralogic.com

A Video Tutorial explaining different Computer Interfaces like PCI,SCSI etc


Video of Kids having fun taking apart a SCSI drive