"I don't see any real intelligence yet," says Chris M. Christian, senior design lead SAN architect at Norfolk Southern Corp., a freight railway company in Norfork, Va. "Advanced intelligence features probably won't arrive till at least the summer, and maybe even later."

Though the products may not be ready quite yet, more intelligence has been added, and a lot more is on the immediate horizon. The driver? The frenzy surrounding information life-cycle management (ILM), which requires a rapid ramp-up in intelligence in order to move data around, regardless of the disk array, platform or servers. As a result, products are now coming onto the market that offer additional switch-based services and hold the promise of easing the storage management burden.

"Moving storage functionality into the switch offers the potential for long-overdue management relief when compared to traditional, host-based techniques," says Fred Moore, president of Horison Information Strategies, a storage consultancy in Boulder, Colo. "Many applications are ideal for this, including virtualization, volume management, backup, replication, storage resource management, hierarchical storage management and security."

Compared with traditional data communications switches and routers, storage switches have always had to provide additional functions that could be classified as intelligent.

Device discovery, for example, is essential for storage networking. Servers are initiators of storage transactions, but storage arrays are passive targets. For servers to find and establish connections with storage arrays, the fabric switch provides fabric log-on services and a simple name server. Once storage devices are registered with the fabric, servers may query the switch to discover potential targets. Likewise, fabric zoning and the mapping and masking of logical unit numbers are intelligent functions designed to ensure that only authorized devices are allowed to communicate across the fabric.