Cisco Systems Inc v. Bockstar Technologies LLC

1. Case Identification

• Case #: IPR2014-01194
• Patent #: Patent 6,233,245
• Filed: July 21, 2014
• Petitioner(s): Cisco Systems, Inc.
• Patent Owner(s): Bockstar Technologies LLC
• Challenged Claims: 1-16

2. Patent Overview

• Title: Method and Apparatus for Management of Bandwidth in a Data Communication Network
• Brief Description: The ’245 patent relates to a method for managing bandwidth in a data network by using a router to dispatch incoming data packets into separate queue buffers based on the source address of the packets. A scheduler then regulates the release of the packets from the various buffers onto a shared physical link.

3. Grounds for Unpatentability

Ground 1: Claims 1-16 are obvious over Nagle

• Prior Art Relied Upon: Nagle (Network Working Group RFC 970, Dec. 1985).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Nagle, published twelve years before the ’245 patent’s filing date, discloses all limitations of the challenged claims. The central argument was that Nagle explicitly teaches the very limitation upon which the patent was allowed during prosecution: dispatching data units based on source address. Nagle describes a packet switch that replaces a single outgoing queue with multiple queues, "one for each source host in the entire network." It further discloses that datagrams are dispatched to an associated queue based on their source address and that the queues are serviced in a round-robin fashion to manage congestion and ensure fairness. This, Petitioner contended, directly maps to the functionality of the independent claims' "data type determination unit" and "scheduler."
  • Key Aspects: This ground’s strength relied on the assertion that the core inventive concept was already publicly disclosed in a foundational networking document not considered by the examiner.

Ground 2: Claims 1-16 are obvious over Nagle in view of Tobagi and Soumiya

• Prior Art Relied Upon: Nagle (RFC 970), Tobagi (Patent 5,381,413), and Soumiya (Patent 5,818,818).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground asserted that even if certain elements were not explicitly disclosed in Nagle, they were well-known in the art as taught by Tobagi and Soumiya. Petitioner argued Nagle provides the key teaching of source-address-based dispatching, which the patent owner had argued was missing from Tobagi and Soumiya during prosecution. Tobagi explicitly discloses a router with a CPU for sorting packets into queues and a throttling algorithm for bandwidth allocation. Soumiya discloses a dedicated "readout scheduler" for releasing packets from different buffers and using data structures to manage packet groups based on quality of service.
  • Motivation to Combine: A POSITA would combine these references because they all address the same technical problem of network congestion management. A POSITA implementing Nagle's source-address queuing scheme would naturally look to well-known components, like the CPU-controlled router in Tobagi or the dedicated scheduler in Soumiya, to build a practical and efficient system. The combination was presented as the application of known components to a known system to achieve predictable results.
  • Expectation of Success: A POSITA would have a high expectation of success, as the combination involved implementing a known queuing logic (Nagle) with standard, widely-used hardware components and scheduling techniques (Tobagi, Soumiya) from the same field of art.

Ground 3: Claims 5, 10, and 15 are obvious over Nagle in view of Braden

• Prior Art Relied Upon: Nagle (RFC 970) and Braden (Network Working Group RFC 1633, July 1994).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground specifically targeted the limitations in dependent claims 5, 10, and 15 requiring a "data structure holding source addresses" to identify the correct queue buffer. While the use of a data structure is inherent in Nagle's system, Braden explicitly describes a "classifier" that uses a database to map each incoming packet to a specific "class" based on its source address. Braden further teaches that all packets in the same class receive the same treatment from a packet scheduler, which implies an association between the class (and thus source address) and a specific queue buffer.
  • Motivation to Combine: A POSITA would combine Nagle and Braden to implement a robust system. When building the source-address-based queuing system of Nagle, it would be a simple and obvious design choice to use a formal data structure, like the classifier database taught by Braden, to efficiently manage the mapping between potentially numerous source addresses and their designated queues.
  • Expectation of Success: Success would be highly predictable, as this combination merely involves using a standard data management technique (a lookup table or database as in Braden) to perform a necessary function (associating source addresses with queues as in Nagle).

• Additional Grounds: Petitioner asserted an additional obviousness challenge against claims 5, 10, and 15 based on the combination of Nagle, Tobagi, Soumiya, and Braden, relying on similar combination rationales.

4. Key Claim Construction Positions

• "router": Petitioner contended that the term "router," appearing in the preamble of claims 1 and 16, is not a claim limitation. In the alternative, should the Board find it limiting, Petitioner proposed the construction "a node in a network that directs incoming packets to the appropriate outgoing links," arguing this construction is met by the "switch" described in Nagle.
• Means-Plus-Function Terms (Claim 16): Petitioner construed the means-plus-function limitations of claim 16 by identifying corresponding structures in the ’245 patent’s specification.
  • storage means was construed as "a memory or any equivalent."
  • data type determination means was construed as "a processor, controller, or any equivalent."
  • scheduler means was also construed as "a processor, controller, or any equivalent."
  • Petitioner argued that the functions performed by these structures were fully disclosed in the prior art combinations.

5. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-16 of Patent 6,233,245 as unpatentable.