On the Microsoft Windows OS, iSCSI has reached a very mature level. On Linux, the Linux-iSCSI project has a refined iSCSI initiator. On the Mac, there are only a few vendors, and most are on their first generation iSCSI protocol drivers for Mac OS X Panther 10.3 and Mac OS X Tiger 10.4 OS. This is all going to change in the next several months.
Apple Computer has a SAN solution, compatible with ADIC’s StorNext File System called xSAN, a new disk paradigm that supports Mac OS X application only. In order to use the xSAN file system, one needs to erase completely and reformat any attached drives, including RAID subsystems.
Currently xSAN is supported through fibre channel networks only, and requires a dedicated ethernet port for metadata. iSCSI allows a traditional gigabit ethernet (GbE) network to become dedicated to storage with a moderate performance decrease. One can install a dedicated single or multiple port PCI card for dedicated GbE storage networking and internet traffic.
ATTO Technologies offers the Xtend SAN and Studio Network Solutions offers the GlobalSAN product. In the near future, expect D-Link to have products ready for market that go beyond the 1 GbE connection, stretching the storage platform to 10 GbE, beyond the range of 4 Gb fibre channel.