PTAB

IPR2019-00372

Hewlett Packard Enterprise Co. v. Parity Networks LLC

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1. Case Identification

2. Patent Overview

  • Title: Method and Apparatus for Transferring a Packet of Data on a Network
  • Brief Description: The ’287 patent describes a method and apparatus for routing data packets from a source node to a destination node, where both nodes reside on a first subnetwork (e.g., a virtual private network, or VPN). The packets are transferred across a second, different subnetwork (e.g., the Internet) by generating a value from the packet’s first header, placing that value into a second header, and using the second header to select one of multiple available paths on the second subnetwork for forwarding the packet.

3. Grounds for Unpatentability

Ground 1: Obviousness over Jagannath and Callon - Claims 1-3, 19, 21-22, 24-27, and 29-32 are obvious over Jagannath in view of Callon.

  • Prior Art Relied Upon: Jagannath (Patent 7,095,740) and Callon (Internet Engineering Task Force Internet-Draft, “A Framework for Multiprotocol Label Switching,” Nov. 21, 1997).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Jagannath discloses the fundamental architecture of the challenged claims, including a method for directing messages through a network comprising a first subnetwork (a VPN) and a second subnetwork (the Internet). Jagannath teaches encapsulating packets with a first header (IP header) and a second header containing a VPN-specific label for routing. However, Petitioner contended that Jagannath does not explicitly teach deriving a value from the first header to enable load balancing across multiple paths. This missing element, Petitioner asserted, is supplied by Callon. Callon describes a framework for Multiprotocol Label Switching (MPLS) that supports multipath routing. Specifically, Callon teaches using a hash function on the source and destination IP addresses (i.e., the first header) to generate a value. This value is then used to split traffic into multiple streams, thereby avoiding packet misordering and enabling load balancing, which directly maps to the core limitations of independent claims 1 and 19. The dependent claims recite features explicitly taught by the combination, such as the first subnetwork being a VPN and the second being the Internet (Jagannath), or the use of a hash operation on IP addresses to derive the value (Callon).
    • Motivation to Combine: The primary motivation asserted was that Jagannath expressly incorporates the MPLS standard that is defined in Callon. Jagannath states that the "VPN-ID is placed in the label field as defined by the Multi-protocol label switching standard, see Callon et al." A person of ordinary skill in the art (POSITA), upon reading Jagannath, would have been directly led to consult Callon to properly implement the MPLS-based system. Furthermore, Callon mandates that MPLS protocol standards "MUST support multipath routing." To create a compliant MPLS system as described by Jagannath, a POSITA would have been motivated to incorporate Callon's teachings on handling multipath, including its disclosed hashing technique for path selection and load sharing.
    • Expectation of Success: Petitioner argued a POSITA would have had a high expectation of success in combining the references. The combination involved applying a standard-mandated technique (Callon's multipath hashing) to the very system designed to use that standard (Jagannath's MPLS/VPN network). This would have been a predictable integration of complementary technologies to achieve the known benefits of efficient and reliable multipath routing.

4. Key Claim Construction Positions

  • Petitioner argued for a specific construction of the limitation "using the second header portion, selecting one of a plurality of paths on the second subnetwork for forwarding of the packet" (recited in claim 1).
  • Proposed Construction: Petitioner contended the phrase should be construed as: "using the derived value in the second header portion, selecting one of a plurality of paths on the second subnetwork for forwarding of the packet, such that different paths are selected for packets having different derived values."
  • Importance: This construction was central to Petitioner's argument because it framed the "inventive concept" as not merely selecting a path, but specifically as load-balancing traffic across different paths based on the derived value. Petitioner supported this construction by pointing to the patent's specification and, critically, to statements made by the patentee during prosecution. The patentee had distinguished the invention from prior art by emphasizing that the "inventive nature" of the process was its ability to use a "new value derived" from the header to "load balance the packets on different paths through the Internet."

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under 35 U.S.C. § 325(d) would be inappropriate.
  • The core of this argument was that the primary prior art references relied upon in the petition, Jagannath and Callon, were never cited or considered by the examiner during the original prosecution of the ’287 patent. Because the Patent Office had not previously been presented with or evaluated this specific combination of prior art, Petitioner argued that the grounds were new and substantial, warranting institution of an inter partes review (IPR).

6. Relief Requested

  • Petitioner requested the institution of an IPR and the cancellation of claims 1-3, 19, 21-22, 24-27, and 29-32 of Patent 6,643,287 as unpatentable under 35 U.S.C. §103.