iSNS is a simple naming, discovery and management protocol, while iSCSI is a communications transport protocol. iSCSI enables communication of devices between each other, and iSNS provides IP storage networks the ability to learn about storage device network addresses, what characteristics they have and what devices are allowed to access them. iSNS provides the same capabilities that Fibre Channel Simple Name Service has traditionally provided in the Fibre Channel world, plus enhancements for authentication and security. Comparing with IP networks, iSNS provides similar capabilities to Domain Name Service (DNS) for IP storage devices. These discovery and management capabilities weren't available for IP storage until iSNS came along.
As a lightweight discovery protocol, iSNS can be deployed in iSCSI adapters and target devices, iSNS servers, and IP Storage switches.
iSNS also facilitates the integration of existing Fibre Channel devices with next-generation iSCSI networks by providing a common device representation model for both iSCSI and Fibre Channel devices. Using iSNS, Fibre Channel device names (i.e. World Wide Names) can be transparently mapped to iSCSI device names and vice-versa to create manageable zones. Why release the iSNS software as open source code? How will this impact the development and adoption of IP storage technologies?
Releasing the iSNS source
Carnegie Mellon University hosts a number of IP Storage projects on their website, such as the IP Storage reflector, Intel's iSCSI Reference Implementation Project, and a URL for downloading the iSNS source code. The iSNS naming service, which functions with all proposed IP Storage protocols, including iSCSI and iFCP, is available for download on the Carnegie Mellon website. What is the significance of iSNS as it relates to IP Storage?
iSNS represents the industry's efforts to bring enterprise class scalability to IP Storage networks, such as those based on iSCSI. With support from industry leaders, customers can rest assured that they will have the tools to build manageable IP storage networks. In addition, with support for both Fibre Channel storage devices and Fibre Channel storage networks, customers will have an ability to integrate existing environments and add new IP Storage environments. Who developed the iSNS protocol?
iSNS was co-developed by a number of different contributors. Co-authors of the iSNS standards-track specification include Cisco Systems, IBM Research, Nishan Systems, Nortel Networks, Pirus Networks, and Vixel Corporation. How is iSNS being used today?
iSNS is being used to demonstrate simple storage device discovery and access control in IP-based storage networks that can scale to enterprise IP solutions.
As a lightweight discovery protocol, iSNS can be deployed in iSCSI adapters and target devices, iSNS servers, and IP Storage switches. Intel is going to support the iSNS protocol by putting iSNS capabilities in its new storage adapter (the Intel PRO/1000 IP Storage Adapter), which will be available later this year, and IBM has already built its first iSCSI storage array. Nishan has already implemented iSNS in its line of IP storage switches. Let us know what you think about the story, e-mail Kevin Komiega, assistant news editor
For more information: iSCSI gets Intel stamp of approval searchStorage Ask the Experts: What to expect from iSCSI searchStorage Technical Tip: IP Storage - Standards linking IP and FC together Download the iSNS source code