Brocade announced Thursday that it has received two U.S. patents for techniques involved in Fibre Channel switching,...
although it won't be collecting royalties for either of them.
Patent No. 6,765,919, awarded on July 20, describes Name Server zoning, also known as "soft zoning". This is one of several techniques governing which devices on a Fibre Channel SAN have access to which storage.
Brocade Communications Systems Inc. decided over a year ago to push its version of soft zoning through the T11 Committee, the ANSI-accredited industry group with responsibility for storage networking.
By submitting its method for soft zoning to the T11 Committee for public consumption, industry analysts said Brocade chose to forfeit its royalty to ensure that others in the industry would interoperate with it. "It's a defensive measure: You don't want to be the orphan out there that's doing it differently," said Randy Kerns, senior analyst at the Evaluator Group.
"We aren't planning any offense strategy around protecting our IP. We want to let people know that this is the correct process for soft zoning," said Jay Kidd, chief technology officer at Brocade.
Switch-based zoning, which limits the visibility of storage to certain users or departments, can be done a couple of ways -- via hardware-enforced zoning, or software-enforced zoning.
In a hard zone, the zone is defined on the basis of the Fibre Channel switch's ports. Only devices in the zone that are physically connected to that switch can communicate. The switch contains a table of port addresses that are allowed to communicate with each other. If a port tries to communicate with a port in a different zone, the frames from the non-authorized port are dropped, and no communication can occur.
Software-enforced zoning is usually based on the use of World Wide Names (WWNs). A WWN is a unique identifier assigned to each Fibre Channel device. In soft zoning, the switch reads incoming frames and ensures that the source and destination addresses (WWNs) have been assigned to the same zone. If these addresses don't correspond, the switch discards the offending frame.
Because it is implemented in the system's circuitry and enforced within the system's routing table, hardware zoning is typically considered more secure than its counterpart, soft zoning.
A Cisco Systems Inc. spokesman pointed out that today, devices can be referred to for zoning purposes by WWN, Fibre Channel address (FCID), and physical port on the switch -- all of which are enforced in hardware and software. "Brocade's older switches could only enforce WWN-based zoning in software, so the term soft zoning and WWN-based zoning were used interchangeably at that time," he said. "We do not use the terms soft or hard zoning, in order to avoid confusing customers. We always use "software-enforced" or "hardware-enforced" when we speak about zoning."
The second patent, No. 6,772,207, awarded on August 4, is titled "System and method of managing Fibre Channel switching device," and describes technology used to monitor and report on the status of Brocade switches in a SAN. It is incorporated into the company's Fabric Manager application for configuration and management of Brocade-based fabrics.
Kerns pointed out that Brocade probably submitted this patent for approval before deciding to support the Storage Networking Industry Association's SMI-S standard, which is intended to improve the interoperability and management of different vendors' switches. "Adhering to SMI-S means this patent is not as important, as this functionality is included in the standard," according to Kerns.
U.S. patent attorney David Cabello, of Wong & Cabello LLP, noted that many companies pursue the patent process, even though they have no intentions of engaging in an offensive strategy.
He said that in some cases, companies use their patent properties as a means of obtaining rights to others' patents by granting a cross license. He added that cross licenses are often granted by companies without money changing hands, or in some cases, money is actually exchanged to make up for the difference in the perceived value of the patent properties, which are swapped. Brocade had no comment on whether it is planning to engage in any cross-licensing.