Internet Small Computer Systems Interface


Internet Small Computer Systems Interface (iSCSI) is a protocol used for linking data storage devices over a network, facilitating data transfers over the internet. This protocol allows clients (initiators) to send SCSI commands (packet data) to SCSI storage devices (targets) on remote servers. It’s a key technology for network storage and allows businesses and organizations to consolidate storage into data centers while providing hosts with the illusion of locally-attached disks.


Internet Small Computer Systems Interface is phonetically pronounced as “In-ter-net Smawl Com-pyu-ter Sis-tems In-ter-face”

Key Takeaways

<ol><li>Internet Small Computer Systems Interface (iSCSI) is a protocol utilized to link data storage devices over a network, effectively enabling communication between the host system and storage device. This allows for seamless data transfers over intranets and the management of storage over long distances.</li><li>One of the main advantages of iSCSI is that it leverages the existing network infrastructure. That is, it utilizes the standard Ethernet network, which makes it a cost-effective solution for storage area networks (SANs). There’s no need for specialized hardware, such as fibre channel.</li><li>iSCSI provides high-level security features, it supports several security protocols, including the Challenge Handshake Authentication Protocol (CHAP) and Internet Protocol Security (IPsec), which help protect important data during transmission.</li></ol>


Internet Small Computer Systems Interface, commonly known as iSCSI, is a crucial technology term due to its vital role in data storage and transfer. It essentially allows two separate networks to connect and interact by linking data storage devices over the Internet, thereby facilitating a distributed network of storage capabilities. This is particularly important for large, data-heavy businesses where efficient data management is key. By using the existing high-speed Internet, iSCSI can transfer data over long distances while maintaining security. Hence, it’s a cost-effective and flexible solution for business continuity, disaster recovery, and other data-intensive applications.


Internet Small Computer Systems Interface (iSCSI) serves a crucial purpose in data storage and transfer over long distances. It is used as an Internet Protocol (IP)-based storage networking standard for connecting data storage facilities. iSCSI makes it possible for locations to link data storage facilities even if they are kilometres apart, providing a reliable and consistent method for data transfer. Utilizing the TCP/IP network, iSCSI packages SCSI commands into TCP/IP packets which can then be delivered across local area networks (LAN), wide area networks (WAN) or the internet.This technology has revolutionized the storage of data by obviating the need for local storage. The essential use of iSCSI is in storage area networks (SAN) as it allows network administrators to consolidate storage into data center storage arrays while allowing hosts to interact with the storage as if it were a local disk. Because of iSCSCi, businesses are able to balance the loads, cluster server operations and perform incremental backups, contributing to a highly efficient and secure work environment.


Internet Small Computer Systems Interface (iSCSI) is a protocol that allows for the transmission of data over intranets. This technology is primarily used in storage area networks (SANs) as a cost-effective alternative to traditional fiber channel. Here are three real-world examples of its applications.1. Data Center Storage: In large data centers, iSCSI is frequently used for creating centralized storage systems. It allows different servers to access and share the same storage, improving efficiency and simplifying data management. Therefore, it is particularly useful for companies dealing with huge amounts of data, such as Facebook or Google.2. Virtualization: iSCSI is heavily used in server virtualization. Companies like VMware use iSCSI to connect virtual machines to the SAN, providing high-performance data storage. It simplifies the management of virtual servers by allowing them to be connected to physical storage through the existing Ethernet network, without the need for additional hardware.3. Disaster Recovery: iSCSI is a crucial technology in business continuity and disaster recovery planning. By using it, companies can replicate their storage over long distances. If a disaster occurs, such as a flood or fire, the data can easily be recovered from the replicated storage. Many data backup and recovery solutions, like those offered by Dell EMC, utilize iSCSI for this purpose.

Frequently Asked Questions(FAQ)

Q: What is an Internet Small Computer Systems Interface (iSCSI)?A: ISCSI refers to a storage networking standard for linking data storage facilities. It enables the transmission of SCSI commands over IP networks, primarily used for Internet access to shared storage devices.Q: How does iSCSI work?A: iSCSI works by transporting block-level data between an iSCSI initiator on a server and an iSCSI target on a storage device. The network link is primarily designed to look like an internal SCSI bus to the operating system.Q: What are the benefits of using iSCSI?A: iSCCSI offers several advantages including cost savings, simplification of storage management, scalability, and improved disaster recovery processes.Q: Is iSCSI secure?A: Yes, iSCSI provides security by using the Challenge-Handshake Authentication Protocol (CHAP) and Internet Protocol Security (IPsec).Q: How does iSCSI differ from Fiber Channel?A: Unlike Fiber Channel, which requires specialized hardware to operate, iSCSI can be used over long distances, and it utilizes the existing Ethernet infrastructure, reducing costs.Q: What is an iSCSI initiator?A: An iSCSI initiator is an entity on the client machine that issues SCSI commands to an iSCSI target on another device.Q: Is iSCSI good for virtualization?A: Yes, iSCSI can be beneficial for virtualization because it allows the storage to be centralized, highly available, and scalable.Q: Can iSCSI run on any network?A: iSCSI can run over any IP network. However, due to its intensity, it’s generally recommended to operate it on a separate, dedicated network for optimal performance.Q: What is an iSCSI target?A: An iSCSI target refers to a storage resource located on an Internet Small Computer System Interface server. It can be sensed and communicated with by an iSCSI initiator.Q: What are the typical applications of iSCSI?A: iSCSI is primarily used in SAN (Storage Area Network) deployments because it allows a broad range of storage networking tasks over standard networks.

Related Tech Terms

  • ISCSI Target
  • ISCSI Initiator
  • Internet Protocol (IP) Address
  • Storage Area Network (SAN)
  • Data Transfer

Sources for More Information

  • Techopedia:
  • Network World:
  • Computer Weekly:
  • Wikipedia:

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