Cisco Systems Inc v. Monarch Networking Solutions LLC

1. Case Identification

• Case #: IPR2020-01678
• Patent #: 8,451,844
• Filed: October 1, 2020
• Petitioner(s): Cisco Systems, Inc.
• Patent Owner(s): Monarch Networking Solutions LLC
• Challenged Claims: 1-10

2. Patent Overview

• Title: Internet Protocol Telecommunications Network
• Brief Description: The ’844 patent describes a method and system for enabling communication between devices in an Internet Protocol version 4 (IPv4) domain and an Internet Protocol version 6 (IPv6) domain. The core technique involves encapsulating IPv4 data packets for routing over an IPv6 network by constructing a routable IPv6 destination address from the original IPv4 destination address and port number.

3. Grounds for Unpatentability

Ground 1: Claims 1-6, 8, and 10 are obvious over Ananda, Wetterwald, and RFC4380

• Prior Art Relied Upon: Ananda (Application # 2004/0107287), Wetterwald (Patent 7,639,686), and RFC4380 (an IETF standard for "Teredo" tunneling).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Ananda taught the core method of encapsulating an IPv4 packet within an IPv6 packet to traverse an IPv6 backbone. Ananda’s communication protocol interface (CPI) constructs an IPv6 destination address from an IPv4 destination address. Wetterwald taught that IPv4 packets routinely include TCP/UDP destination port numbers and described systems for performing IPv6-to-IPv4 address and port translation. RFC4380 explicitly disclosed constructing a "Teredo IPv6 address" that includes a UDP port number and an IPv4 address to facilitate tunneling.
  • Motivation to Combine: A POSITA would combine these references to improve upon Ananda's system. Specifically, a POSITA would be motivated to incorporate the destination port number into the constructed IPv6 address, as taught by Wetterwald and RFC4380. The motivation stemmed from the known benefits of embedding port information, such as increased efficiency by avoiding the need for separate option headers and enhanced security by enabling the detection of spoofed traffic, a well-known network security concern.
  • Expectation of Success: A POSITA would have a high expectation of success because Ananda’s method for constructing an IPv6 address left 32 unallocated bits (filled with zeros), providing ample space to insert a 16-bit destination port number. The combination involved applying known techniques (concatenation) to achieve a predictable result.

Ground 2: Claim 7 is obvious over Ananda, Wetterwald, RFC4380, and RFC4271

• Prior Art Relied Upon: Ananda (Application # 2004/0107287), Wetterwald (Patent 7,639,686), RFC4380, and RFC4271 (an IETF standard for Border Gateway Protocol 4, "BGP-4").
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon the combination in Ground 1 and added RFC4271 to address the limitations of claim 7, which recites advertising network addresses. RFC4271 described BGP, the standard protocol for exchanging routing and reachability information between routers on the internet. This includes advertising sets of destinations.
  • Motivation to Combine: A POSITA would be motivated to incorporate BGP, as taught by RFC4271, into Ananda's network. This would allow Ananda's CPI devices to advertise the IPv4 addresses they could reach to other routers in the IPv4 and IPv6 domains. This is a fundamental requirement for routing in a complex network, ensuring that other devices know the correct path to send packets to their destination.
  • Expectation of Success: Success would be expected because advertising routes using a well-known protocol like BGP was a standard, commonplace technique in network design.

Ground 3: Claim 9 is obvious over Ananda, Wetterwald, RFC4380, and RFC1918

• Prior Art Relied Upon: Ananda (Application # 2004/0107287), Wetterwald (Patent 7,639,686), RFC4380, and RFC1918 (an IETF standard for "Address Allocation for Private Internets").
• Core Argument for this Ground:
  • Prior Art Mapping: This ground targeted claim 9, which adds limitations related to obtaining an IPv4 address, a range of port numbers, and a range of authorized IPv6 addresses. RFC1918 provided the standard framework for using private IPv4 addresses within an enterprise and recommended that such private addresses not be revealed on public links. It also taught using authority servers to manage address allocation and control visibility.
  • Motivation to Combine: A POSITA would be motivated to apply the principles of RFC1918 to the Ananda/Wetterwald/RFC4380 system. Ananda already disclosed the use of private IPv4 addresses. A POSITA would follow the clear guidance of RFC1918 to implement an authorization scheme to manage the address space, thereby creating a range of "authorized" IPv6 addresses corresponding to the private IPv4 hosts. This would enhance security and adhere to well-established best practices for network architecture.

4. Key Claim Construction Positions

• "domain" (all claims): Petitioner argued that this term did not require construction and should be given its plain and ordinary meaning. However, if construction were deemed necessary, Petitioner proposed it should be construed as "network." Petitioner contended the claims are unpatentable under any reasonable construction, including those requiring common control or single administrative authority, as Ananda’s subnets could be configured to meet these criteria.
• "means for" limitations (claims 5-7, 9, 10): Petitioner identified the functions for each means-plus-function limitation and mapped them to corresponding structures disclosed in the ’844 patent, primarily a processor (251/261) and memory (255/265) within a home gateway or access node. Petitioner then argued that the prior art disclosed equivalent structures performing the identical functions.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under Fintiv was inappropriate. The key reasons asserted were:
  • The parallel district court litigation (E.D. Tex.) was in its very early stages, with minimal investment by the parties or the court.
  • The scheduled trial date of May 3, 2021, was highly uncertain because the court had eight other cases scheduled for trial on the same day, making it likely the trial would be delayed until after the Board's Final Written Decision (FWD).
  • The strong merits of the petition weighed heavily in favor of institution to avoid the inefficiency of a potentially unnecessary trial on claims that are likely invalid.
• Petitioner also argued that denial under §325(d) was inappropriate because the core prior art references (Ananda, Wetterwald, RFC4380) were not considered by the Examiner during prosecution.

6. Relief Requested

• Petitioner requested the institution of an inter partes review and cancellation of claims 1-10 of Patent 8,451,844 as unpatentable under 35 U.S.C. §103.