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A single director-class switch can replace multiple smaller switches while offering growth flexibility, high availability and a bevy of advanced features.
The heart of any Fibre Channel storage-area network (FC SAN) is the switching equipment that connects the host servers with the storage systems. This switching equipment performs basic connectivity between FC devices and can also:
- Determine the type of FC devices that are connected
- Handle FC zoning functions
- Typically allow connections to other Fibre Channel switches to extend the storage network
There are two basic classes of FC switching equipment: directors and switches. And while they both perform the same fundamental functions, there are significant differences between the two switch classes.
Basic FC switches generally have a fixed number of ports and provide basic switching functions with limited scalability and redundancy within the switch. This type of FC switch is available today from Brocade Communications Systems Inc., Cisco Systems Inc. and QLogic Corp.
At the high end of the switch spectrum are the directors, generally referred to as director-class switches. Directors are designed and built with scalability and high availability in mind. The term "director" has its heritage in the IBM ESCON Directors of the early 1990s, which were some of the first versions of storage switching equipment used for mainframes. In earlier days, there
|Brocade vs. Cisco: A little history|
Brocade Communications Systems Inc., founded in 1995, developed its own Fibre Channel (FC) switches and was an early leader in the FC switch market. It's also integrated technologies from the other FC switching companies it has bought or inherited, like McData Corp., which Brocade acquired in late 2006. McData had its own line of FC switches and directors and, at one time, had the vast majority of the FC director-class switch market. Brocade's "M-Series" products come from the McData product line. Previously, McData had acquired switch vendor Computer Network Technology (CNT) Corp. in early 2005; before that, CNT had purchased Inrange Technologies Corp. in 2003, which had its own high port-count FC directors.
Cisco Systems Inc., a long-time player in Ethernet switching, announced its first FC switch in 2002 and has been growing that product family since then. Currently, Brocade has the edge in the FC switch and director market, but Cisco is a strong competitor.
This was first published in April 2010