PTAB

IPR2021-00331

Cisco Systems Inc v. Estech Systems Inc

Log In
Key Events
Petition
petition Intelligence

1. Case Identification

2. Patent Overview

  • Title: Information Handling System And Method For Throttling Data Sent From A Workstation To A Telephone
  • Brief Description: The ’684 patent describes a method for managing network traffic in a Voice over IP (VoIP) system. The method involves "throttling" or reducing data transmission from a workstation to a telephone to prioritize the transfer of time-sensitive audio information between the telephone and a multimedia server, thereby preventing voice quality degradation due to network congestion.

3. Grounds for Unpatentability

Ground 1: Obviousness over Chiu - Claims 29-41 are obvious over Chiu.

  • Prior Art Relied Upon: Chiu (Application # 2002/0071424).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Chiu disclosed all architectural elements of the challenged claims, including an information handling system with a multimedia computer (workstation), an IP telephony peripheral (telephone), a phone server (multimedia server), and a network connecting these components. The system in Chiu routes data packets from the computer through the telephone to the network.
    • Motivation to Combine (for §103 grounds): This is a single-reference ground. Petitioner asserted that Chiu expressly identified the problem of "packet collisions" and taught the use of "collision avoidance mechanisms well known in the networking arts" to solve it. A person of ordinary skill in the art (POSITA) would have understood that throttling data from the workstation was a well-known, predictable solution to avoid such collisions and prioritize real-time voice packets, as suggested by Chiu.
    • Expectation of Success: A POSITA would have had a high expectation of success because implementing known throttling techniques, such as the "jabbering" process admitted as a "standard Ethernet process" in the ’684 patent itself, was a routine optimization to achieve Chiu's stated goal of reliable real-time data transmission.

Ground 2: Obviousness over Chiu and Bustini - Claims 29-41 are obvious over Chiu in view of Bustini.

  • Prior Art Relied Upon: Chiu (Application # 2002/0071424) and Bustini (Patent 5,313,454).
  • Core Argument for this Ground:
    • Prior Art Mapping: Chiu provided the foundational VoIP system architecture. Bustini provided a specific, detailed "feedback control system for congestion prevention" that explicitly taught controlling the transmission rate of lower-priority "bursty traffic" in the presence of high-priority voice traffic.
    • Motivation to Combine: Petitioner contended that while Chiu identified the need for "well-known" collision avoidance, it did not specify a particular mechanism. A POSITA seeking to implement Chiu's system would have been motivated to look to prior art like Bustini, which detailed a specific algorithm for the exact problem: managing mixed voice and data traffic. Combining Bustini's specific congestion control method with Chiu's system was a straightforward implementation of Chiu’s express teaching.
    • Expectation of Success: Success was expected because implementing Bustini's software-based algorithm into Chiu's hardware architecture was a trivial integration of a known solution to a known problem, yielding only predictable improvements in voice quality.

Ground 3: Obviousness over Lecomte and Bechtolsheim - Claims 29-41 are obvious over Lecomte in view of Bechtolsheim.

  • Prior Art Relied Upon: Lecomte (Patent 5,065,425) and Bechtolsheim (Patent 6,515,963).

  • Core Argument for this Ground:

    • Prior Art Mapping: Lecomte disclosed an earlier digital telephone system where a computer connects to a network through a digital phone, with the phone acting as a switch for both voice and data. Bechtolsheim taught a more modern, sophisticated congestion control mechanism for high-speed networks that ensures quality-of-service for time-critical packets, such as VoIP, by using a dynamic buffer limit (DBL) to throttle or drop lower-priority packets.
    • Motivation to Combine: A POSITA would have been motivated to update the older architecture of Lecomte to function with modern, higher-speed packet-switched protocols like TCP/IP. To do so, the POSITA would incorporate an advanced congestion control algorithm like the one taught by Bechtolsheim to ensure the integrity of time-sensitive audio signals, a specific goal of Bechtolsheim's invention.
    • Expectation of Success: The combination represented an arrangement of known parts, with Lecomte providing the system architecture and Bechtolsheim providing a known method for traffic management. This would have yielded the predictable result of a functional, modern VoIP system with reliable quality of service.

  • Additional Grounds: Petitioner asserted additional obviousness challenges against claim 34 based on combinations including Kramer (Patent 6,658,027), which taught the use of a jitter buffer to smooth out variable packet arrival rates in VoIP communications.

4. Key Claim Construction Positions

  • Petitioner argued that the challenged claims are obvious regardless of whether the claim terms are given their plain and ordinary meaning or the constructions proposed in co-pending district court litigation. Key terms included:
    • "a data server coupled to the hub": Petitioner contended that under any reasonable interpretation, this was disclosed by the prior art's description of standard network components.
    • "sufficiently throttling the data": Petitioner argued this broadly covers any method of reducing data flow to prioritize audio, a concept widely taught in the prior art for preventing congestion and packet collision.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under Fintiv would be inappropriate for several reasons:
    • Petitioner was not a defendant in the parallel district court proceedings, and this IPR was its primary opportunity to challenge the patent's validity as it related to its own products.
    • The scheduled trial dates in the parallel litigation were speculative and likely to be delayed due to court backlogs and the COVID-19 pandemic, whereas the PTAB proceeding would adhere to a fixed statutory deadline.
    • The investment in the parallel proceedings was minimal at the time of filing, with no Markman hearing having occurred.
    • The petition presented a strong case on the merits, particularly the single-reference obviousness ground over Chiu, which weighed heavily in favor of institution.

6. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 29-41 of the ’684 patent as unpatentable.