DCT
6:20-cv-00727
WSOU Investments LLC v. Hewlett Packard Enterprises Co
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: WSOU Investments, LLC d/b/a Brazos Licensing and Development (Delaware)
- Defendant: Hewlett Packard Enterprise Company (Delaware)
- Plaintiff’s Counsel: Brown Rudnick LLP; The Mort Law Firm, PLLC
- Case Identification: 6:20-cv-00727, W.D. Tex., 11/06/2020
- Venue Allegations: Venue is alleged to be proper based on Defendant maintaining regular and established places of business within the Western District of Texas, including an office in Austin, and having committed acts of infringement in the district.
- Core Dispute: Plaintiff alleges that Defendant’s network routers and switches, which support Multiprotocol Label Switching (MPLS), infringe a patent related to multi-criteria path determination in a label-switched communication network.
- Technical Context: The technology at issue, MPLS, is a fundamental routing technique used in high-performance telecommunications networks to direct data from one node to the next based on short path labels rather than long network addresses, improving traffic flow and management.
- Key Procedural History: This First Amended Complaint was filed following an initial complaint served on August 18, 2020. The filing states that it moots a prior motion to dismiss filed by the Defendant. The date of service of the initial complaint is asserted as the date Defendant gained actual knowledge of the patent-in-suit, which is relevant to the allegations of willful and indirect infringement.
Case Timeline
| Date | Event |
|---|---|
| 2002-12-17 | ’832 Patent Priority Date |
| 2008-10-28 | ’832 Patent Issue Date |
| 2020-08-18 | Date of service of the initial complaint |
| 2020-11-06 | First Amended Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 7,443,832 - "Device for Determining Switching Paths in a Label Switched Communication Network in the Presence of Selection Attributes," issued October 28, 2008
The Invention Explained
- Problem Addressed: The patent describes a problem in computer networking where calculating the best path for data traffic based on a single criterion, such as the shortest path, can lead to network congestion on that path while other suitable routes remain underutilized (’832 Patent, col. 4:39-47). Methods that consider multiple constraints sequentially are described as being computationally inefficient (’832 Patent, col. 4:58-64).
- The Patented Solution: The invention proposes a device that determines a data path by simultaneously evaluating at least two different criteria (e.g., bandwidth, path duration). The device calculates possible paths, deduces a theoretical "ideal solution" based on the best possible performance for each criterion, and then assigns an "interest value" to each real path based on its proximity to this ideal solution. A path is then selected from a classified list, allowing for a more balanced and efficient use of network resources (’832 Patent, Abstract; col. 4:25-38).
- Technical Importance: This multi-criteria approach to path selection represented a method for more sophisticated traffic engineering, enabling network administrators to balance competing performance demands (e.g., speed vs. reliability) to better manage Quality of Service (QoS) for different types of data streams (’832 Patent, col. 4:25-31).
Key Claims at a Glance
- The complaint asserts infringement of at least Claim 1 (’832 Patent, Compl. ¶41).
- Independent Claim 1 recites the key elements of the device:
- A memory means for storing a table of correspondences between service data and criteria, and a descriptive structure with network topology and utilization data.
- A processing means for:
- (a) receiving a path set-up request and determining at least two criteria from the table;
- (b) ensuring the connectivity of the network routers based on data in the descriptive structure;
- (c) calculating possible paths between a departure and destination node based on the criteria, and then deducing an "ideal solution" from the performance of those paths;
- (d) assigning each possible path an "interest value" based on the ideal solution and classifying the paths accordingly; and
- (e) selecting a path from the classified list and associating a label with the data stream for switching.
III. The Accused Instrumentality
Product Identification
- The complaint accuses the HPE HSR6800 Router Series, HPE A880 Router Series, and the HPE 5820X Switch Series (collectively, the "Accused Products") (Compl. ¶21).
Functionality and Market Context
- The Accused Products are described as routers and switches that support MPLS services and are built with a "multi-core distributed processing architecture" capable of high forwarding and switching capacities (Compl. ¶¶21, 25).
- The complaint alleges that these products provide a feature for configuring "Constraint-Based Label Switched Paths" (CR-LSPs), which are used to determine a path in a network of routers (Compl. ¶29). This functionality allegedly uses the "Constraint-based Shortest Path First (CSPF)" algorithm to calculate a path that complies with specified constraints, such as QoS parameters, bandwidth, and priority (Compl. ¶33). The complaint provides a network diagram illustrating the establishment of a Label Switched Path (LSP) through multiple Label Switched Routers (LSRs) (Compl. p. 9, Figure A).
IV. Analysis of Infringement Allegations
’832 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a memory means for storing a table of correspondences between sets of service data and information data representative of at least two chosen criteria and a descriptive structure containing information data representative of a state of utilization and of a topology of the network | The Accused Products allegedly use a Traffic Engineering Database (TEDB) to store TE attributes (criteria) for links, network topology information, and working conditions of links (Compl. ¶¶30-31). | ¶¶30-31 | col. 4:7-14 |
| a processing means for: a) receiving a path set-up request containing a set of service data associated with a stream to be switched, and for determining in said table at least two criteria stored in corresponding relationship to said set of service data | The Accused Products allegedly provide for "Dynamic CR-LSP establishment" where a path is calculated based on service data (e.g., QoS parameters) and criteria (e.g., bandwidth, affinity) (Compl. ¶33). | ¶33 | col. 4:15-21 |
| b) ensuring the connectivity of said multiplicity of label switched routers, on the basis of information data stored in said descriptive structure | The Accused Products allegedly ensure connectivity by using information about link state stored in the TEDB and provide a feature to configure a "failed link timer" to manage link status (Compl. ¶¶34-35). The complaint includes a table showing the commands to configure this timer (Compl. p. 11, Figure B). | ¶¶34-35 | col. 4:22-24 |
| c) calculating from among said label switch routers possible paths... and then deducing an ideal solution from performances of said possible paths on at least one of said criteria | The Accused Products allegedly use the CSPF algorithm to calculate possible paths by pruning non-compliant links and "deduces an ideal solution based on the constraints" (Compl. ¶¶36-37). The complaint includes a table describing the configuration of a "tie breaker in CSPF" for when multiple paths have the same metric (Compl. p. 12, Figure C). | ¶¶36-37 | col. 4:25-31 |
| d) assigning each possible path an interest value taking account of said ideal solution and then classifying said possible paths taking account their respective interest values | When multiple paths have the same metric, a tie-breaking method is allegedly used, and "based on the interest values the paths are classified" (Compl. ¶39). | ¶39 | col. 4:32-35 |
| e) selecting a path from among said classified possible paths and then associating with said stream to be switched a label representative of said selected path so that said labeled stream is switched via said path | A path is allegedly selected from the classified paths, and the Label Distribution Protocol (LDP) is used to advertise labels and reserve resources along the calculated path (Compl. ¶¶39-40). | ¶¶39-40 | col. 4:35-38 |
Identified Points of Contention
- Scope Questions: Claim 1 uses broad functional terms such as "ideal solution" and "interest value". The infringement analysis may turn on whether the accused CSPF algorithm, including its method for "tie-breaking" between paths with the same metric (Compl. p. 12, Figure C), falls within the scope of these terms. A question for the court will be whether simply selecting a path from a group of equal-metric paths using a tie-breaker is equivalent to the patent's more structured process of deducing a theoretical ideal and classifying paths based on their distance from it.
- Technical Questions: A key technical question is whether the accused products' CSPF algorithm performs the specific function of "deducing an ideal solution" as described in the patent. The patent details a process of creating a theoretical ideal path composed of the best-performing segments for each criterion, which may not correspond to any single, real path (’832 Patent, col. 7:33-51). It is an open question whether the evidence will show the accused products perform this specific type of calculation or if they use a different method to find a "shortest, constraint-compliant path" (Compl. ¶33).
V. Key Claim Terms for Construction
The Term: "ideal solution"
- Context and Importance: This term appears in claim elements 1(c) and 1(d) and is central to the patented method of path selection. The definition of this term is critical because the infringement allegation depends on showing that the accused products "deduce" such a solution and then use it to classify paths.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: Parties arguing for a broader scope may point to general language suggesting it is simply the optimal outcome, such as the patent's high-level objective to find the most appropriate path (’832 Patent, col. 8:21-24).
- Evidence for a Narrower Interpretation: The specification provides a specific, technical definition, stating the "ideal solution Z(Я) is a vector" composed of "the best performance value observed over the possible paths" for each individual criterion. It explicitly notes that this ideal path "does not necessarily correspond to one of the possible paths" (’832 Patent, col. 7:33-49). This language may support a narrower construction requiring the calculation of a theoretical, possibly non-existent, benchmark.
The Term: "interest value"
- Context and Importance: This term from claim element 1(d) defines the metric used to classify the potential paths. Its construction is tied directly to the meaning of "ideal solution".
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: One could argue this term covers any numerical score or ranking used to compare paths, consistent with the complaint's allegation that a "tie-breaking method" classifies paths based on their "interest values" (Compl. ¶39).
- Evidence for a Narrower Interpretation: The patent specification and dependent claim 11 describe a specific method for calculating this value: "a weighted Tchebychev function, as a function of differences between the performance of said possible path and the corresponding optimum value of said ideal solution" (’832 Patent, col. 8:5-15; Claim 11). This may support a narrower definition requiring the value to be a calculated distance from the "ideal solution".
VI. Other Allegations
Indirect Infringement
- The complaint alleges induced infringement, asserting that HPE gained knowledge of the ’832 Patent upon service of the initial complaint on August 18, 2020 (Compl. ¶43). It further alleges that HPE intends to cause infringement by providing customers with product descriptions, operating manuals, configuration guides, and training programs that instruct users on how to configure and use the accused MPLS features (Compl. ¶¶45-46).
Willful Infringement
- The willfulness claim is based on allegations that HPE had knowledge of the patent and its infringement as of the date the initial complaint was served and has continued its allegedly infringing activities notwithstanding this knowledge (Compl. ¶43).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: can the patent’s terms "ideal solution" and "interest value", which are described in the specification with specific mathematical properties, be construed to cover the functions of the accused Constraint-based Shortest Path First (CSPF) algorithm and its associated tie-breaking rules?
- A key evidentiary question will be one of functional equivalence: does the accused products' pathfinding algorithm perform the specific, two-step logical function required by Claim 1—first deducing a theoretical "ideal solution" and then classifying real paths based on their calculated distance from that ideal—or does it employ a fundamentally different technical operation to identify a single, optimal, compliant path?