PTAB

IPR2014-00139

Reloaded v. Parallel Networks LLC

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: System and Method for Caching Data
  • Brief Description: The ’262 patent discloses methods and systems for dynamic, distributed data caching within a network community of peers. The invention is directed to a process where a first peer generates a content request, communicates with a central “master” entity to determine a second peer associated with the requested content, and then retrieves the content directly from that second peer.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1, 5-10, 14-19, and 23-27 under 35 U.S.C. §102 by Chase

  • Prior Art Relied Upon: Chase (Patent 5,944,780).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Chase, which was not considered during prosecution, discloses every limitation of the challenged claims. Chase describes a distributed caching environment where “user stations” (the claimed “peers”) in a network are available to each other. When a first station requests data, it queries a central “directory server” (the claimed “master”) that maintains a directory of cached content across the network. The directory server identifies a second station that holds the data, and the first station then retrieves the data directly from the second station’s cache, anticipating the method of independent claim 1. Petitioner further mapped the limitations of corresponding system and computer-readable medium claims to the structures and software processes disclosed in Chase.

Ground 2: Anticipation of Claims 1, 5-10, 14-19, and 23-27 under §102 by Povey

  • Prior Art Relied Upon: Povey (“A Distributed Internet Cache,” a 1997 conference paper).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Povey's hierarchical distributed cache system also anticipates the claims. In Povey, a client associated with a “leaf cache” (a first peer) requests an object. The leaf cache queries its parent or “upper-level” node (the master) for the location of the object. The upper-level node determines which other leaf cache (a second peer) in the community holds a copy of the object and returns a “pointer” to the requesting leaf cache. The first peer then uses this pointer to retrieve the object from the second peer, directly mapping to the patented method.

Ground 3: Claims 2, 4, 11, 13, 20, and 22 are obvious over Chase in view of Smith

  • Prior Art Relied Upon: Chase (Patent 5,944,780) and Smith (Patent 6,341,311).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner argued that while Chase teaches the core method of claim 1, Smith provides the teachings for dependent claim 2, which adds the step of retrieving content from an origin server when it is unavailable at the second peer. Smith explicitly addresses this scenario in a distributed proxy server array, disclosing that if a proxy server receives a request for content it does not have, it retrieves the object from the Internet (the origin server), stores it in its local cache, and then provides it to the requesting peer.
    • Motivation to Combine: A POSITA would combine Chase and Smith to address the known and common problem of a cache miss in the distributed system taught by Chase. Smith provides a well-understood, simple solution to improve the system's robustness and efficiency. Both references are in the same field of endeavor and address the same problems of network bottlenecks and redundant data transfer.
    • Expectation of Success: A POSITA would have had a high expectation of success. The combination involved applying a known technique (retrieving from an origin server on a cache miss) to an existing architecture (Chase’s distributed cache) to achieve the predictable result of a more fault-tolerant and efficient caching system.

  • Additional Grounds: Petitioner asserted additional anticipation challenges against all claims based on Kangasharju (a 1999 web caching workshop paper) and numerous obviousness challenges. These obviousness grounds relied on combinations including Chase in view of Scharber; Chase and Smith in view of Scharber; Povey in view of Chase; and Kangasharju in view of Chase, arguing similar motivations to combine to improve caching efficiency and handle cache misses.

4. Key Claim Construction Positions

  • Petitioner argued that several terms in system claim 19 are means-plus-function limitations governed by pre-AIA 35 U.S.C. §112, ¶6, and proposed constructions based on the specification.
    • “means for generating a content request…”: The stated function is generating a request for content at a first peer. Petitioner identified the corresponding structure disclosed in the ’262 patent as a web browser or other Hypertext Transport Protocol (HTTP) client.
    • “means for determining a second peer…”: The stated function is determining a second peer associated with the requested content. Petitioner identified the corresponding structure as one or more general-purpose computers of a first peer and a master, programmed to perform the algorithm of examining an allocation list to determine which peer would cache the content.
    • “means for communicating the location request to a master…”: The stated function is communicating the location request to the master. Petitioner identified the corresponding structure as a DSL modem, cable modem, LAN, or other “always-on” Internet connection.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-27 of the ’262 patent as unpatentable.