Copper for Fibre Channel SANs
Although it was initially designed for use with fibre optical cable, Fibre Channel works well at shorter distances over copper cable, in such installations as storage area networks. In fact, the specification lists several different kinds of copper media which can support Fibre Channel.
The most common form of copper for Fibre Channel is shielded, twisted pair using DB-9 connectors -- what looks like shielded telephone wire, in other words. However it is important to realize that copper cable for Fibre Channel needs to meet higher performance standards than conventional telephone wire. Trying to re-use existing phone wiring to carry Fibre Channel signals is usually false economy, especially if the cable contains multiple splices. It might work and it might not. Worse, sub-standard cabling can be the source of all kinds of unobvious problems.
Properly specified and installed copper cable works fine for shorter distances, such as within a building, at speeds up to 100 MB/s.
For more information on the Fibre Channel specification and how it applies to SAN installations, see the tutorial at the University of New Hampshire Web site (www.iol.unh.edu/training/fc/fc_tutorial.html).
About the author: Rick Cook has been writing about mass storage since the days when the term meant an 80K floppy disk. The computers he learned on used ferrite cores and magnetic drums. For the last twenty years he has been a freelance writer specializing in storage and other computer issues.
Did you like this tip? Whether you did or not, why not let us know. Drop us an email and sound off.
Fibre Channel for SANs
Author : Alan Frederic Benner
Publisher : McGraw-Hill
Published : Mar 2001
PRACTICAL ROADMAP FOR DESIGNING AND DEPLOYING A SANFibre Channel has come into its own as the defining network architecture for Storage Area Networks (SANs), which are proving critical for managing the volume and complexity of data generated by Internet-era applications. Fibre Channel for SANs, by Dr. Alan F. Benner, shows you how Fibre Channel works, how it integrates with other protocols and systems, and how to implement it to create a SAN for fast access to mass storage. It walks you through the ANSI standard's 5 levels, from the physical transmission level through interfaces to upper layer protocols, and demonstrates mapping SCSI and IP over Fibre Channel. You get a wealth of timesaving illustrations and practical suggestions for troubleshooting.