PTAB

IPR2017-01711

Cavium Inc v. Alacritech Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Obtaining a Destination Address So That a Network Interface Device Can Write Network Data Without Headers Directly Into Host Memory
  • Brief Description: The ’699 patent describes a method for offloading network protocol processing to improve system performance. The patented method involves a network interface device (NID) that receives network packets, provides a header portion (e.g., a session-layer header) to the host computer, and in response, obtains a destination memory address from an application running on the host. The NID then uses this address to transfer the data portions of subsequent packets directly into the host's application memory via Direct Memory Access (DMA), bypassing the host CPU and without transferring the network or transport layer headers.

3. Grounds for Unpatentability

Ground 1: Obviousness over Kiyohara and SMB - Claims 1-3, 6, 7, 10, 11, 13, 16, and 17 are obvious over Kiyohara in view of SMB.

  • Prior Art Relied Upon: Kiyohara (Patent 5,237,693) and SMB ("Protocols for X/Open PC Networking: SMB, Version 2," a technical standard).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner argued that Kiyohara disclosed the foundational elements of the challenged claims. Kiyohara teaches an "intelligent board system" comprising a network interface coupled to a host computer. This interface offloads the processing of lower protocol layers (transport, network, data link) while the host computer processes upper layers (session, application). Kiyohara’s system receives packets, separates headers from data, and places the data into a "data storage area" (destination) whose location is obtained from an application on the host computer. This process avoids unnecessary data copying and host CPU processing of lower-layer headers, thus meeting the core limitations of independent claims 1, 7, and 13 regarding receiving packets, offloading processing, and transferring data without headers.

    However, Petitioner asserted that Kiyohara, while teaching the use of a session layer, does not disclose a specific session layer protocol or the mechanism by which its header is analyzed to obtain the data destination. The SMB protocol standard fills this gap. SMB is a session-layer protocol for file and printer sharing that operates over standard transport protocols like TCP/IP. An SMB header contains command codes (e.g., for read/write operations) and fields that a host application would analyze to determine the destination and length of data in a response. Petitioner contended that implementing the well-known SMB protocol on Kiyohara's host computer would inherently involve the host analyzing the SMB (session layer) header to determine where to store file data, thereby teaching the "analyzing" and "obtaining a destination" limitations of the independent claims.

    Dependent claims were argued to be obvious for similar reasons. For example, claims 2, 7, and 13 require providing a session layer header to the computer, which is a necessary step in the combined system where the host processes the SMB session. Claims 3, 10, and 16 require identifying the application by a transport layer port number, which Petitioner argued was a fundamental and well-known feature of TCP, a protocol explicitly disclosed in Kiyohara. Claims 6, 11, and 17, which require the network interface to perform the data transfer, were argued to be an obvious implementation choice, particularly given Kiyohara’s disclosure of a "coprocessor for network communication" on its interface and the common use of DMA for such transfers at the time.

    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Kiyohara and SMB to create a complete, high-performance networking system. Kiyohara provides an efficient hardware architecture for offloading protocol processing for peripheral sharing but lacks a specific session layer protocol. SMB was the primary industry-standard session layer protocol for the exact same purpose: network file and printer sharing. A POSITA seeking to implement Kiyohara's system would naturally look to a standard, widely-used protocol like SMB to handle the session layer functionality. The combination would yield the predictable result of a high-speed file sharing system leveraging Kiyohara's hardware acceleration and SMB's standardized application-level functions.

    • Expectation of Success: A POSITA would have a high expectation of success. Kiyohara’s system was designed to work with standard layered protocols like OSI and TCP/IP. The SMB specification explicitly states it can be implemented over these same protocols. Combining them would involve standard software engineering practices to integrate a known protocol (SMB) onto a compatible hardware architecture (Kiyohara), presenting no undue technical burden.

4. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-3, 6, 7, 10, 11, 13, 16, and 17 of the ’699 patent as unpatentable.