PTAB

IPR2022-00833

CommScope Inc v. TQ Delta LLC

Log In
Key Events
Petition

1. Case Identification

2. Patent Overview

  • Title: Packet Retransmission and Memory Sharing
  • Brief Description: The ’055 patent discloses a communications system and method for selectively retransmitting data packets based on Quality of Service (QOS) requirements. The system differentiates between packets requiring a low packet error rate (low-PER), which are retransmitted for reliability, and packets requiring low latency, which are not retransmitted to minimize delay.

3. Grounds for Unpatentability

Ground 1: Claims 1, 5, 10, 11, 15, and 20 are obvious over Kawakami.

  • Prior Art Relied Upon: Kawakami (Application # 2005/0036497).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Kawakami taught all limitations of the challenged claims in its disclosure of a mobile communication system. Kawakami handled two frame types based on QOS: "acknowledgement type" frames for data that tolerates delay but not errors, and "unacknowledgement type" frames for voice communications that tolerate errors but not delay. Petitioner contended these directly correspond to the ’055 patent’s low-PER and low-latency packets. Kawakami’s system stored acknowledgement frames in a retransmission buffer after transmission, added a "sequence number" to their headers for error tracking, and retransmitted them if lost. In contrast, unacknowledgement frames were not buffered, their headers did not include a sequence number, and they were not retransmitted, allegedly mapping to all limitations of independent claims 1 and 11.

Ground 2: All challenged claims are obvious over Reynders.

  • Prior Art Relied Upon: Reynders (“Practical TCP/IP and Ethernet Networking,” 2003).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Reynders, a foundational textbook, described the claimed invention as standard industry practice for TCP/IP networking. Reynders taught the use of two primary protocols: TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). TCP, analogous to the first packet type, was described as a reliable protocol that uses sequence numbers and positive acknowledgement with retransmission to ensure data integrity, which inherently requires storing packets in a retransmission buffer. UDP, analogous to the second packet type, was described as an unreliable, low-overhead protocol for real-time data (e.g., streaming video) that does not use sequence numbers or retransmission and is not buffered. Petitioner argued that Reynders disclosed using a "Protocol" field in the IP header to indicate whether a packet is TCP or UDP, fulfilling the claim limitation of a header identifying the packet type.

Ground 3: All challenged claims are obvious over RFC 791, RFC 793, and RFC 768.

  • Prior Art Relied Upon: RFC 791 (“Internet Protocol”), RFC 793 (“Transmission Control Protocol”), and RFC 768 (“User Datagram Protocol”).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the combination of these foundational internet standards rendered the claims obvious. RFC 793 (TCP) taught a reliable protocol that assigns a "Sequence Number" to data, places a copy of transmitted segments in a "retransmission queue" (buffer), and retransmits data if an acknowledgement is not received. Conversely, RFC 768 (UDP) taught a simple, unreliable protocol where delivery is not guaranteed, retransmission is not performed, and the header does not contain a sequence number. RFC 791 (IP) described the underlying packet structure, including a "Protocol" field in the IP header that specifies whether the data payload should be handled by the TCP or UDP protocol, thus identifying the packet type and fulfilling all limitations of the independent claims.
    • Motivation to Combine: A POSITA designing or analyzing an internet-based communication system would combine these foundational RFCs because they form the core TCP/IP protocol suite and are explicitly designed to operate together. RFC 791 depicts TCP and UDP as the protocols operating directly above the IP layer, making their combined consideration essential for a functioning network.
    • Expectation of Success: A POSITA would have a high expectation of success, as the protocols defined in these RFCs were the de facto standard for internet communications and were designed for seamless interoperability.

4. Key Claim Construction Positions

  • Petitioner stated it accepted prior constructions from a related district court case for two terms:
    • "transceiver": "communications device capable of transmitting and receiving data wherein the transmitter portion and receiver portion share at least some common circuitry"
    • "packet": "a grouping of bytes"
  • Petitioner asserted that no other claim constructions were necessary to resolve the controversy.

5. Arguments Regarding Discretionary Denial

  • §325(d) Arguments: Petitioner argued against discretionary denial under §325(d), asserting that the prior art and arguments were not the same or substantially the same as those considered during prosecution. While Kawakami was cited in an Information Disclosure Statement, Petitioner contended there was no evidence the Examiner substantively reviewed it. The other primary references, Reynders and the RFCs, were not before the Examiner at all.
  • Fintiv Arguments: Petitioner argued against discretionary denial under Fintiv, stating that the trial date in the parallel district court litigation was scheduled approximately 17 months after the complaint was filed, with a high likelihood of delay, making it probable that a Final Written Decision would issue before trial. Petitioner also contended it was diligent in filing the petition and that there was minimal overlap between the few claims asserted in the district court (11, 17, and 19) and the broader set of claims challenged in the IPR.

6. Relief Requested

  • Petitioner requests institution of IPR and cancellation of claims 1, 4-5, 7, 9-11, 14-15, 17, 19-20 as unpatentable.