Adaptec Flags iSCSI Patent Claim

Adaptec Inc. (Nasdaq: ADPT) today notified the Internet Engineering Task Force (IETF)'s IP Storage working group that the company may own intellectual property pertaining to the iSCSI specification.

While Adaptec's claims may only apply narrowly to a certain implementation of iSCSI -- and the company says it will license any patented technology on "reasonable, non-discriminatory terms" -- it could nonetheless be a fly in the ointment as the first standards-compliant iSCSI products start hitting the market in the next few months (see IP SANs: Coming of Age and iSCSI's Second Act).

"Adaptec has made a patent application that may relate to the work underway in the IPS working group, specifically to the work derived from draft-ietf-ips-iscsi-20.txt," the company's statement says.

The iSCSI draft 20 referred to is the version the IETF ratified in February. The notice was sent to the IPS mailing list by Todd Sperry, an Adaptec engineer who is a contributor to the group (see iSCSI Gets Go-Ahead).

Adaptec says its patent application describes "a method and process for calculating a CRC on data received out of order without having to store and assemble the data." CRC (Cyclic Redundancy Check) is an error-checking technique used to guarantee the accuracy of data transmissions.If any patents are issued to Adaptec "with claims that are necessary for practicing this standard," the company's statement continues, other vendors will be able to obtain the right to implement and use the technology "under openly specified, reasonable, non-discriminatory terms." An Adaptec spokesman was unable to provide any additional information by press time.

Earlier this week, Adaptec announced that it has started shipping its first iSCSI adapter, the ASA-7211, which the company says provides 138-Mbyte/s full duplex throughput using an ASIC that performs TCP offload functions (see Adaptec Shipping iSCSI).

David Black, senior technologist at EMC Corp. (NYSE: EMC) who co-chairs the IETF IP Storage working group, says the Adaptec claims appear to not be applicable to all implementations.

He says they "may be applicable to people who are building seriously hot-rodded hardware." He adds that Adaptec's patent application could also potentially affect implementations of standards being developed by the IETF's Remote Direct Data Placement (RDDP) working group. RDDP refers to the ability to place data directly from a network adapter into application buffers, without intensive CPU usage.

Intellectual property issues relating to iSCSI have cropped up before. A little over a year ago, Lucent Technologies Inc. (NYSE: LU) and Phoenix Technologies Ltd. (Nasdaq: PTEC) claimed to own patents covering the Secure Remote Password (SRP) authentication scheme that's part of the iSCSI spec; both companies subsequently agreed to license their patents on a "fair and equitable basis" to other vendors (see iSCSI in Patent Pickle and iSCSI Spec Set).Todd Spangler, US Editor, Byte and Switch