When talking about storage area networks (SAN’s) it would be remiss if one were to leave out the presence of the ISCSI devices. ISCSI or Internet Small Computer System Interface seeks to bring the current hardware standard to a more usable form in today’s evolving SAN architecture. The ISCSI devices are designed to be used for linking data across multiple areas, utilizing TCP/IP in order to transfer data to a remote storage location. The interface allows local computers to access remote storage locations via virtual disk mounting, a feature that has been present in many operating systems for at least a decade. Combining this readily available feature with SAN protocols, local computers can acquire read/write access to the community storage device for whatever purpose required. Here we take a look at ISCSI storage and how it measures up.
What is ISCI?
ISCI is a protocol that allows for the transfer of data over a TCP/IP network for the purpose of storing it at a remote location. The SCSI device resides at the remote location and takes its directives from the TCP/IP network. Block data is transferred from the host machine, via a TCP/IP connection to a controller attached to a remote SCSI device elsewhere. The distance is limited only by access to the network. It can be utilized in a number of different scenarios, inclusive of both LAN and WAN storage and backup. It can also be used to serve as a surrogate cloud storage, although without the levels of security that is associated with current cloud storage solutions.
Topology of an ISCSI Network
Ideally, an ISCSI network consists of a series of computers linked directly to ISCSI initiators that send information to the SCSI SAN. It is possible to route the connections through a single dedicated switch that deals with all data moving across the network. However, it would be more practical to install a dedicated Ethernet controller solely for use with the ISCSI system in order to avoid network traffic problems and errors in routing. It is relatively simple to install since it is Ethernet-based and doesn’t need a specific type of hardware to operate effectively.
ISCSI systems are poised to compete with fibre-channel systems for SAN purposes. Both technologies have their benefits and their drawbacks. For a business considering using an SAN, they should examine what the business needs and see which one of the solutions is more practical. As technology advances, we will see more and more solutions for storage area networks. At present, the ISCSI is one of the best that is available. Its low startup and maintenance costs make it an economically responsible decision for a business just starting off on the road to establishing an SAN.
