PTAB

IPR2020-01276

DISH Network LLC v. Sound View Innovations LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method of Reducing Start-up Latency for Live Streaming Media
  • Brief Description: The ’796 patent discloses a network architecture and method for decreasing playback delay for live streaming multimedia (SM). The system employs "helper servers" (HSs) that function as caching and streaming agents to distribute live SM broadcast objects from a content server to clients, thereby reducing start-up latency.

3. Grounds for Unpatentability

Ground 1: Obviousness over Geagan and Vishlitzky - Claims 1-3, 5-7, 13-15, 18, 20, 21, 24, 25, 27, and 29 are obvious over Geagan in view of Vishlitzky.

  • Prior Art Relied Upon: Geagan (Patent 6,263,371) and Vishlitzky (Patent 5,737,747).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Geagan disclosed the core network architecture recited in the claims, including a content server, clients, and proxy servers that function as the claimed "helper servers" for distributing live streaming content. Geagan's proxies buffer streams to reduce packet loss and can serve multiple clients. However, Petitioner contended Geagan does not explicitly teach a "pre-configured playout history (PH) buffer." To supply this limitation, Petitioner asserted that Vishlitzky taught a video server system that pre-configures and allocates memory for popular video streams using a "sliding window" cache, which is analogous to the claimed pre-configured PH buffer. Vishlitzky also taught a method for determining whether to service a request from this pre-configured buffer (for a "popular" movie) or from a standard disk array (for an "unpopular" movie). Petitioner argued Geagan's system, when serving a subsequent user from its buffered "seamed stream," provides a higher effective data rate than serving an initial user from the main content source, thus meeting the "higher than a standard data rate" limitation of claim 1.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA) would have been motivated to combine Geagan's live streaming proxy system with Vishlitzky's advanced, pre-configured caching techniques. The goal would be to improve performance for popular live events, which are known to attract many viewers, by using the pre-configured "sliding window" buffer taught by Vishlitzky to reduce latency, a problem both references aimed to solve.
    • Expectation of Success: A POSITA would have had a high expectation of success in combining the references because both described systems based on industry-standard network protocols and architectures (e.g., TCP/IP, ATM), making their integration predictable.

Ground 2: Obviousness over Geagan, Vishlitzky, and Zheng - Claims 1-3, 5-7, 13-15, 18, 20, 21, 24, 25, 27, and 29 are obvious over Geagan in view of Vishlitzky and Zheng.

  • Prior Art Relied Upon: Geagan (Patent 6,263,371), Vishlitzky (Patent 5,737,747), and Zheng (a 1998 publication from IEEE GLOBECOM '98).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground incorporated the arguments from Ground 1 and added Zheng to address a potentially narrower interpretation of claim 1[c], which requires "reducing the startup latency by initially filling the client's playout buffer as rapidly as possible with a higher data rate." Petitioner argued that Zheng explicitly taught a "Fast Buffer Fillup" (FBF) scheme for video-on-demand systems to reduce startup delay. Zheng's method involved transmitting data at a high Peak Cell Rate (PCR) to quickly fill the client's buffer and then switching to a standard Average Cell Rate (ACR) for normal playback. This directly taught servicing a request with an initial high data rate followed by a subsequent standard data rate, as claimed.
    • Motivation to Combine: A POSITA, having already combined Geagan and Vishlitzky to create an efficient live streaming system, would be further motivated to incorporate Zheng’s FBF technique. Zheng provided an advantageous and effective method for further reducing startup delay, which was a primary feature of all three disclosed technologies.
    • Expectation of Success: The combination was asserted to be predictable because all three references described systems using standard protocols. Combining the server model of Zheng, which relies on ATM networking, with Geagan's proxy device was well within the skill of a POSITA, as "IP over ATM" was a well-known technique.

4. Key Claim Construction Positions

  • Petitioner argued that the prior art invalidates the claims under any plausible construction, including those adopted in related district court litigation. The petition focused on several key terms:
  • "pre-configured playout history (PH) buffer": This term was central to the invalidity argument. Petitioner addressed the narrowest construction from district court: "a buffer that...is manually configured before the live SM object is requested and permanently maintained in memory thereafter." Petitioner argued that Vishlitzky's teaching of pre-allocating large memory blocks for "popular movies" to be served from a sliding window cache met even this narrow construction when applied to Geagan's system.
  • "live streaming media broadcast object": Addressing the construction's requirement for "non-segmented" data, Petitioner asserted that Geagan's "live broadcasts of streaming content" were inherently non-segmented. This was based on the Patent Owner's own arguments during the original prosecution of the ’796 patent, where it distinguished prior art by stating that live objects are created "on-the-fly" and cannot be segmented like pre-stored files.
  • "partially servicing/service/serviced...": Petitioner contended this term did not require a narrow interpretation of rapidly filling a client buffer. However, it argued that even if it did, the combination with Zheng (Ground 2) explicitly taught such a method.

5. Relief Requested

  • Petitioner requested that the Board institute an inter partes review of claims 1-3, 5-7, 13-15, 18, 20, 21, 24, 25, 27, and 29 of the ’796 patent and find them unpatentable and cancelled.