DCT

5:25-cv-06441

Cisco Systems Inc v. Dynamic Mesh Networks Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 3:25-cv-06441, N.D. Cal., 07/31/2025
  • Venue Allegations: Plaintiff Cisco Systems, Inc. alleges that venue is proper in the Northern District of California as Defendants conduct business in the district and the individual defendants reside there.
  • Core Dispute: Plaintiff seeks a declaratory judgment that its wireless networking and communication products do not infringe eight patents asserted by Defendants related to the management, operation, and data handling of wireless mesh networks.
  • Technical Context: The technology at issue involves methods for creating self-organizing, adaptive, and resilient wireless mesh networks, which are foundational for modern enterprise, metropolitan, and mobile Wi-Fi deployments.
  • Key Procedural History: The complaint states that this declaratory judgment action follows two prior lawsuits filed by Defendant MeshDynamics against Cisco in the Eastern District of Texas asserting the same eight patents. Mesh Dynamics voluntarily dismissed those actions without prejudice, and its counsel allegedly represented that it would sue Cisco again, creating the basis for the current controversy.

Case Timeline

Date Event
2002-10-28 Earliest Priority Date ('952, '243, '537 Patents)
2005-11-04 Priority Date ('762 Patent)
2006-06-19 Priority Date ('385 Patent)
2008-09-02 '952 Patent Issued
2008-11-24 Priority Date ('852, '000 Patents)
2009-01-30 Priority Date ('691 Patent)
2009 Parties allegedly met to discuss a potential partnership
2011-02-08 '243 Patent Issued
2011-02-22 '385 Patent Issued
2013-07-02 '762 Patent Issued
2013-08-20 '852 Patent Issued
2013-08-27 '691 Patent Issued
2015-06-02 '000 Patent Issued
2022-06-22 Defendant allegedly sent letter providing notice of infringement
2022-06-21 '537 Patent Issued
2025-05-05 First E.D. Tex. lawsuit filed by MeshDynamics (2:25-cv-00472 Litigation)
2025-06-06 Second E.D. Tex. lawsuit filed by MeshDynamics (2:25-cv-00606 Litigation)
2025-07-31 E.D. Tex. lawsuits voluntarily dismissed without prejudice
2025-07-31 Complaint for Declaratory Judgment Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 7,420,952 - "High performance wireless networks using distributed control"

  • Issued: September 2, 2008 (Compl. ¶40).

The Invention Explained

  • Problem Addressed: The patent’s background describes the inefficiency and lack of scalability in wireless networks with centralized control, where all devices must connect directly to a single root access point, leading to poor overall network throughput as distances increase ('952 Patent, col. 2:20-31).
  • The Patented Solution: The invention proposes a decentralized, adaptive wireless network where individual relay nodes intelligently select their connection path, either to the main root or an intermediate parent node, to optimize performance. A central access server can set high-level policies (e.g., prioritizing low latency or high throughput), but the individual nodes execute these policies autonomously, allowing the network to self-configure for optimal performance ('952 Patent, col. 3:6-21; col. 4:1-6).
  • Technical Importance: This distributed control architecture enables the creation of more scalable, resilient, and higher-performing mesh networks that can be deployed without extensive manual configuration or site surveys ('952 Patent, col. 4:7-12).

Key Claims at a Glance

  • The complaint identifies independent claim 1 as an exemplary asserted claim (Compl. ¶¶50-51).
  • Essential elements of claim 1 include:
    • A method of controlling a wireless mesh network.
    • Configuring the network with relay nodes, each having a first radio interface for parent communication and a second dual-purpose radio interface for child and client communication.
    • Determining that a first relay node requires a channel selection change.
    • Dynamically selecting a second relay node to become the new parent for the first relay node.
    • Making a channel selection change to meet a performance requirement.
    • A temporal requirement that, prior to this dynamic selection, the new parent node was a "sibling node" of the first relay node.

U.S. Patent No. 7,885,243 - "High performance wireless networks using distributed control"

  • Issued: February 8, 2011 (Compl. ¶41).

The Invention Explained

  • Problem Addressed: The patent, which shares a specification with the ’952 Patent, addresses the challenge of optimizing routing paths in a wireless mesh network to balance performance criteria such as throughput and latency ('243 Patent, col. 2:25-50).
  • The Patented Solution: The invention claims a network system where AP nodes autonomously select and switch parent nodes based on defined "communication criteria." A key aspect of the solution is the use of a "route path dataset," which comprises identifiers for each node in the path to the root. An AP node uses this dataset, for instance by selecting the parent that offers the "shortest route path dataset," to make dynamic routing decisions ('243 Patent, Abstract; col. 10:1-10).
  • Technical Importance: This approach provides a specific data structure and algorithmic framework enabling network nodes to make decentralized and dynamic routing optimizations, enhancing the network's adaptability and performance ('243 Patent, col. 4:1-21).

Key Claims at a Glance

  • The complaint identifies independent claim 12 as an exemplary asserted claim (Compl. ¶¶55-56).
  • Essential elements of claim 12 include:
    • A wireless mesh network with an access server, root nodes, and AP nodes.
    • An AP node containing datasets and a "means for switching" its parent node based on network parameters.
    • One dataset is a "route path dataset" comprising an identifier for the parent node appended to that parent's own route path dataset.
    • "Communication criteria" that instruct the AP node to select a parent based on factors including whether a potential parent is in communication with a root node or has a root node in its route path dataset.
    • A criterion that instructs the AP to associate with the parent node having the "shortest route path dataset" among all available parent nodes.

U.S. Patent No. 7,894,385 - "Mobility extensions for wireless multiple radio mesh"

  • Issued: February 22, 2011 (Compl. ¶42).
  • Technology Synopsis: The patent addresses the problem of maintaining network connectivity for mobile nodes in a multi-radio mesh environment. The solution involves a mesh node using a dedicated scanning radio to discover potential new parent nodes while other radios continue to handle data traffic, with packet buffering and a token-based coordination system used to manage the handoff without losing data ('385 Patent, Abstract).
  • Asserted Claims: The complaint identifies claim 2 as an exemplary asserted claim (Compl. ¶60).
  • Accused Features: Cisco's "'Mesh' Wi-Fi equipment and solutions, including Cisco's Access Points ('APs'), wireless controllers and control systems" (Compl. ¶¶3, 60).

U.S. Patent No. 8,477,762 - "Self-forming VoIP network"

  • Issued: July 2, 2013 (Compl. ¶43).
  • Technology Synopsis: The patent addresses the inability to make VoIP calls when a network segment is isolated from its central Session Initiation Protocol (SIP) server. The invention allows VoIP nodes within such an "isolated cluster" to build and maintain a local, distributed SIP registry by exchanging information directly, enabling VoIP calls to be established and maintained within the cluster without external connectivity ('762 Patent, Abstract).
  • Asserted Claims: The complaint identifies claim 1 as an exemplary asserted claim (Compl. ¶65).
  • Accused Features: "VoIP collaboration products and solutions, including, for example, Cisco WebEx" (Compl. ¶¶5, 65).

U.S. Patent No. 8,514,852 - "Real time packet transforms to avoid re-transmission"

  • Issued: August 20, 2013 (Compl. ¶44).
  • Technology Synopsis: The patent addresses performance degradation caused by re-transmissions of corrupted packets in real-time data streams like video. The solution involves modifying a standard packet to include redundant information along with a "position offset reference number" that points to it. A receiving or relaying device that detects a checksum error can use this embedded information to repair the packet locally, avoiding the delay of a full re-transmission request ('852 Patent, Abstract).
  • Asserted Claims: The complaint identifies claim 1 as an exemplary asserted claim (Compl. ¶70).
  • Accused Features: "Cisco networking equipment and solutions, including, for example, Cisco SD-WAN solutions and equipment with Forward Error Correction ('FEC')" (Compl. ¶¶5, 70).

U.S. Patent No. 8,520,691 - "Persistent mesh for isolated mobile and temporal networking"

  • Issued: August 27, 2013 (Compl. ¶45).
  • Technology Synopsis: The patent addresses how a structured mesh network can maintain its topology and internal connectivity when it becomes disconnected from an external network. The invention describes a network that can function in two configurations: "connected" and "isolated." When isolated, one of the nodes is designated as an "isolated network root," allowing the other nodes to maintain their parent-child relationships and form a persistent tree structure for continued intra-network communication ('691 Patent, Abstract).
  • Asserted Claims: The complaint identifies claim 1 as an exemplary asserted claim (Compl. ¶75).
  • Accused Features: Cisco's "'Mesh' Wi-Fi equipment and solutions," including APs and wireless controllers (Compl. ¶¶3, 75).

U.S. Patent No. 9,049,000 - "Real-time packet transforms to avoid re-transmissions"

  • Issued: June 2, 2015 (Compl. ¶46).
  • Technology Synopsis: This patent is related to the '852 Patent and addresses packet corruption in real-time data streams. The claimed method involves modifying a packet to include redundant information and a pointer. Upon detecting a checksum mismatch, a receiving device can retrieve the redundant data using the pointer to replace the corrupted portion of the packet, thereby avoiding a re-transmission ('000 Patent, Abstract).
  • Asserted Claims: The complaint identifies claim 1 as an exemplary asserted claim (Compl. ¶80).
  • Accused Features: "Cisco networking equipment and solutions, including, for example, Cisco SD-WAN solutions and equipment with Forward Error Correction ('FEC')" (Compl. ¶¶5, 80).

U.S. Patent No. 11,368,537 - "High performance wireless network"

  • Issued: June 21, 2022 (Compl. ¶47).
  • Technology Synopsis: This patent, from the same family as the '7420952 and '7885243 patents, describes a wireless mesh network organized in a tree structure. It details an automatic connection process where a Mesh Access Point (MAP) node selects a single parent from potential candidates based on criteria defined by an access server, such as throughput (signal strength) and latency (hop count), to establish its routing path to an external network ('537 Patent, Abstract).
  • Asserted Claims: The complaint identifies claim 1 as an exemplary asserted claim (Compl. ¶85).
  • Accused Features: Cisco's "'Mesh' Wi-Fi equipment and solutions," including APs and wireless controllers (Compl. ¶¶3, 85).

III. The Accused Instrumentality

Product Identification

  • The complaint identifies products in two categories based on prior litigation:
    1. "'Mesh' Wi-Fi equipment and solutions, including Cisco's Access Points ('APs'), wireless controllers and control systems" (Compl. ¶3).
    2. "VoIP collaboration products and solutions, including, for example, Cisco WebEx" and "Cisco networking equipment and solutions, including, for example, Cisco SD-WAN solutions and equipment with Forward Error Correction ('FEC')" (Compl. ¶5).

Functionality and Market Context

  • The complaint asserts that Cisco is a "worldwide leader in developing, implementing, and providing the technologies behind networking products and services" (Compl. ¶14). As this is a complaint for declaratory judgment of non-infringement, it does not describe the specific functionality of the accused products in detail. Instead, it makes conclusory allegations that the products do not possess the features required by the asserted patent claims (Compl. ¶¶51, 56, 61, 66, 71, 76, 81, 86).

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

'952 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Non-Infringing Functionality Complaint Citation Patent Citation
[1a] ...a second dual purpose radio interface configurable to both relay traffic from the child relay node and to communicate with a client node that is not a relay node... The complaint alleges the Accused Products do not include this feature. ¶51 col. 5:57-65
[1d] making a channel selection change The complaint alleges the Accused Products do not perform this step. ¶51 col. 8:17-19
[1e] wherein prior to being dynamically selected, the second relay node was a sibling node of the first relay node The complaint alleges the Accused Products do not meet this temporal condition. ¶51 col. 8:17-22

Identified Points of Contention

  • Scope Questions: A primary dispute may concern the interpretation of "radio interface." The question for the court will be whether a single, multi-function physical radio within a Cisco AP can meet the claim's requirement for both a "first radio interface" and a "second dual purpose radio interface," or if the claim requires two distinct hardware structures.
  • Technical Questions: A factual question will be whether the dynamic topology of Cisco's mesh networks ever satisfies the claim's temporal requirement that a node selected as a new parent must have been a "sibling node" of the child node immediately prior to the selection.

'243 Patent Infringement Allegations

Claim Element (from Independent Claim 12) Alleged Non-Infringing Functionality Complaint Citation Patent Citation
[12pre] A wireless mesh network... The complaint alleges the Accused Products do not form the claimed network. ¶56 col. 5:1-6
[12e] ...wherein an AP node includes a means for switching two-way data communication from a first associated parent node to a second associated parent node... The complaint alleges the Accused Products do not include this feature. ¶56 col. 9:18-24
[12f] ...one of the datasets contained in an AP node comprises a route path dataset comprising an identifier for the associated parent node appended to the route path dataset... The complaint alleges the Accused Products do not utilize the claimed dataset structure. ¶56 col. 7:18-22
[12g] ...communication criteria comprises instructions for the AP node to select the associated parent node wherein an available parent node is selected... if a root node is contained in the available parent node's route path dataset The complaint alleges the Accused Products do not use this selection criterion. ¶56 col. 7:23-36
[12h] ...wherein the communication criteria further comprises instructions for the AP node to associate with a single suitable parent node wherein the route path dataset of the parent node is the shortest route path dataset of all available parent nodes. The complaint alleges the Accused Products do not use this selection criterion. ¶56 col. 10:1-10

Identified Points of Contention

  • Scope Questions: The term "means for switching" is subject to 35 U.S.C. § 112(f) and its construction will be critical. The court will need to identify the corresponding structure in the patent's specification—the parent selection algorithm—and the dispute will center on whether Cisco's products use a structurally equivalent algorithm.
  • Technical Questions: The analysis will raise the evidentiary question of whether Cisco’s routing protocols generate, maintain, and use a data structure that functions as the claimed "route path dataset" by appending identifiers and then selecting a new parent based on the "shortest" resulting dataset.

V. Key Claim Terms for Construction

Term: "second dual purpose radio interface" ('952 Patent, Claim 1)

  • Context and Importance: Cisco's non-infringement argument for the '952 patent is based in part on this term (Compl. ¶51). The case may turn on whether a single physical radio, capable of multiple functions, can satisfy the claim's requirement for two distinct "interfaces."
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim uses the term "interface," which could be construed functionally rather than structurally. The specification's description of a dual-purpose node acting as both a relay and an access point could support an interpretation where logical function, not physical hardware count, defines the interface ('952 Patent, col. 5:62-65).
    • Evidence for a Narrower Interpretation: The specification explicitly discloses an implementation where nodes "have two radios: one to communicate with its clients... [and one for] relaying traffic" ('952 Patent, col. 5:57-62). This language may be used to argue that the claimed "interfaces" require separate physical radio structures.

Term: "route path dataset" ('243 Patent, Claim 12)

  • Context and Importance: Cisco's non-infringement allegation rests on its products not using this specific data structure for routing decisions (Compl. ¶56). The definition of this term is central to whether Cisco's dynamic routing algorithms fall within the scope of the claim.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent describes the dataset's function as tracking the connection route back to the root ('243 Patent, col. 7:18-20). This may support a construction covering any data structure that accumulates node identifiers along a path for routing purposes.
    • Evidence for a Narrower Interpretation: The specification provides a concrete example: "in FIG. 4B, the route path for 005 is 000 002 005" ('243 Patent, col. 7:18-20). This suggests a specific structure of concatenated identifiers, and the claim limitation requiring selection of the "shortest" dataset (col. 10:7-10) could be construed to mean the path with the fewest enumerated hops.

VI. Other Allegations

Indirect Infringement

  • The complaint does not provide sufficient detail for analysis of indirect infringement, as it is a declaratory judgment action seeking a finding of non-infringement.

Willful Infringement

  • The complaint does not allege willfulness. However, it notes that Defendant Francis daCosta sent a letter to Cisco on or about June 22, 2022, which was alleged in the prior litigation to have placed Cisco on actual notice of its alleged infringement (Compl. ¶7). This fact may become the basis for a future willfulness allegation by Defendants.

VII. Analyst’s Conclusion: Key Questions for the Case

  • A core issue will be one of structural scope: can the claim term "radio interface," described in the context of distinct parent-facing and child-facing functions, be construed to cover a single, time-multiplexed radio in Cisco’s accused products, or is it limited to the specification's embodiment of two separate physical radios?
  • A key evidentiary question will be one of algorithmic equivalence: do Cisco's proprietary routing protocols for mesh networks employ a data structure and selection logic that is structurally and functionally equivalent to the claimed "route path dataset," which requires appending node identifiers and selecting a parent based on the "shortest" resulting dataset?
  • A third central question will be one of temporal operation: for the '8514852 patent, the dispute will require a detailed factual analysis of Cisco's network topology over time to determine if a node selected as a new parent was, as the claim requires, a "sibling node" immediately prior to the parent-child relationship being formed.