SANs are storage for high rollers — or are they? Storage AreaNetworks are specialized storage systems that allow multi-user access,as server-attached storage does, but also provide high performance,which SAS cannot. To overcome the adoption barrier that the high costof traditional SANs impose, Studio Network Solutions has introduced anew family of storage products based on the recently adopted iSCSIprotocols instead of the more complex and costly Fibre Channel standardthat the company already supports. Its globalSAN™ iSCSI storagesolution uses the universal Internet Protocol (IP), upon which both theInternet and Ethernet are based, to transport encapsulated SCSIcommands. This encapsulation, or packaging, allows IP-based storage touse commodity infrastructure for rapid, cost-effective transport ofblock-level I/O data over existing high-speed networks.
Unlike NAS, or network-attached storage, which provides relativelysluggish performance of only file-level data, iSCSI allows for trueblock-level manipulation over LANs, MANs and WANs (local, metropolitanand wide-area networks). This means that, rather than moving entirefiles from storage to a local node or computer for processing and thensaving the modified file in its entirety back to the NAS, iSCSI allowsfor reading and writing inside of a file while it resides on theremote storage device.
The iSCSI protocol takes into account the myriad problems typicallyfound in a local, metropolitan or wide-area networked environment.Trouble is, although Microsoft has a Windows-native iSCSI initiatoravailable for download, Apple does not. So, Studio Network Solutionshad to build Mac OS X — native iSCSI initiator software andprovide its own iSCSI Host Bus Adapter — another piece of thepuzzle not available for Mac OS. The company’s HBA is a multi-portPCI-X card with support for link aggregation and jumbo frames, featuresthat considerably improve throughput.
With all of the low-level pieces in place, the Studio NetworkSolutions development team needed to provide a means for the end-userto control the day-to-day operations of his or her storage network.Because they already had full management and networked storagefunctionality in their existing SANmp™ software, they extended itto include the necessary bits to interoperate with iSCSI, as well. Thismeans that Windows, Mac and mixed or heterogeneous network clients canall dynamically share both Fibre Channel and iSCSI storage assetswithout compromise.
One of the problems with any network, including storage-centricnetworks, is security. The iSCSI standard provides for strongencryption using the IPsec or IPsecure protocol for transmission ofsensitive data over unprotected networks. When asked what securityissues an end-user should consider, Eric Newbauer, director ofoperations for SNS, provides some details: “An iSCSI-based SANcan actually be configured to be quite secure. The amount of securitymeasures that clients will realistically want to take [will] dependupon whether they will be transferring data over their LAN or over theInternet. If it’s the former and they want to keep their data safe fromthe outside world, the obvious answer would be to create a closed,dedicated network or configure their firewall to block access to theiSCSI ports from the outside. For public networks — like theInternet — they can set up a VPN using the IPsec protocol.”IPsec’s strong encryption employs the Advanced Encryption Standard, theindustry and government choice for mission-critical security.
Gary Holladay, SNS president and chief systems designer, sums up thevalue of the company’s globalSAN product line, stating, “Mostimportantly, they offer performance nearing that of Fibre Channel overmulti-Gigabit Ethernet. We’ll certainly continue developing andsupporting our line of A/V SAN PRO Fibre Channel systems, but webelieve there’s a substantial number of production companies thatsimply don’t have the budget and/or the need for a pure Fibre Channelsolution. For those that already have a SAN or have been thinking aboutimplementing one, we’ve really opened up their options. Support foriSCSI will now be included with our existing SANmp volume sharingsoftware.
“This means that, in addition to concurrently supporting Macand Windows on the same network, the standard version enablesvolume-level shared storage networking for both FC and IP-basedSANs,” he continued. “For those that just need support foriSCSI, they’ll have the option to use the new iSANmp version of thesoftware. The realm of platforms and protocols that our softwaresupports enables us to accommodate practically any facility’s needs— large or small.”