Storage subsystems outfit Zitel Corporation, which until now has made a living feeding off the Unisys mainframe market is making eyes at the open systems market with its recently released CASD- II/Enterprise storage system. Supporting both heterogeneous server and fault-tolerant clustered servers the system includes the company’s own CASD Cached Actuator Storage Device technology, which the Fremont, California-based company describes as a major departure from conventional string or CPU cache devices. CASD incorporates a high capacity cache that is physically integrated into the drive module. Coupled with sophisticated algorithms, Zitel says CASD delivers striking performance improvements over more conventional string cache storage systems. The cache size is dedicated to a single disk spindle and can be 64Mb to 256Mb. This large cache size and the fact that it is an actuator level cache has created a virtual SSD solid state disk environment characterized by high input/ output rates and very fast access times, say Zitel. In the past, says the company, cost has been a major barrier to this kind of technology both in terms of DRAM memory, and of the microprocessors which are the cache’s engines. Zitel is positioning CASD between SSD and disk-based media with its adaptive caching capabilities. CASD comes with four major sub-units: the engine – a microprocessor-based controller including a high capacity DRAM cache and a 12Mb/sec internal bus tightly coupled to three intelligent SCSI controllers; a high-capacity, high performance 3 or 5 inch disk drive; power supply and power management; and battery backup. CASD-II/Enterprise uses a modular design that enables expansion of storage capacities from 10s of Gb to terabytes, while simultaneously scaling in both connectivity and performance, says Zitel. Each CASD- II/Enterprise storage module is a self contained, integrated unit with host/disk controller supporting a fully configurable Dual Port/Dual Host Fast SCSI interface that offers both multiple host and dual path configurations in HI-RAS, clustered, and heterogeneous server environments. It comes with intelligence- based global cache in each CASD-II/Enterprise module and can be scaled from 32Mb to 512Mb of ECC protected, non-volatile memory. Prices are dependent on configuration. The seventeen year old NASDAQ quoted company authorized a two-for-one split of its common stock in the form of a stock dividend back in November. The stock dividend increased the number of shares outstanding from approximately 7.5 million to 15 million shares. The company now has over a hundred employees in the US as well as thirteen based in Europe.
