Derivative works — US Patent 8234705

Defensive Disclosure and Prior Art Derivations for US Patent 8,234,705

This document provides a detailed technical disclosure of derivative inventions and improvements based on the core concepts described in US Patent 8,234,705. The intent of this disclosure is to place these concepts into the public domain, thereby rendering them as prior art for the purposes of patentability examination. Each concept is described with sufficient detail to be enabled by a person skilled in the art.

Derivations Based on Independent Claim 1: A Method for Quarantining a Host

1. Material & Component Substitution

Derivative 1.1: FPGA-Based Hardware Quarantine Enforcement

Enabling Description: This variation replaces the general-purpose processor-based quarantine determination with a Field-Programmable Gate Array (FPGA) co-processor integrated into the network switch or gateway. The FPGA is loaded with a hardware description language (HDL) implementation of a finite state machine (FSM) that performs the quarantine logic. Upon receiving a connection request (e.g., a DHCP DISCOVER packet), the FPGA inspects the packet's MAC address against an on-chip block RAM (BRAM) containing a list of compromised or non-compliant devices. If a match is found, the FPGA directly manipulates the switch's forwarding tables to reroute all traffic from the corresponding port to a dedicated quarantine VLAN, except for traffic destined for the remediation server's MAC address. This hardware-level enforcement reduces latency from milliseconds (in a software-based system) to nanoseconds, making it suitable for line-rate enforcement in 100/400 Gbps networks. The determination of whether a host is "required to be quarantined" is offloaded to this dedicated hardware circuit, providing a deterministic, low-latency response.

Mermaid.js Diagram:

graph TD
    A[Host Connects: DHCP DISCOVER] --> B{FPGA Co-Processor};
    B --> C{Inspect MAC Address};
    C --> D{Lookup in On-Chip BRAM};
    D -- Match Found --> E[Reconfigure Switch Fabric];
    E --> F[Redirect Port Traffic to Quarantine VLAN];
    F --> G[Allow Traffic to Remediation Server MAC];
    D -- No Match --> H[Allow Normal Network Access];

2. Operational Parameter Expansion

Derivative 2.1: Cryogenic Datacenter Network Quarantine

Enabling Description: This method is adapted for network hardware operating in a cryogenic environment (e.g., below 77 Kelvin) for high-performance computing or quantum computing systems. All network components, including switches and routers, are designed to operate at these temperatures. The quarantine determination process accounts for the unique physical layer characteristics, such as superconducting interconnects. The "limited access" state is defined not just by logical ports but by allocating a specific, power-limited optical wavelength to the quarantined host. The quarantine server itself is a specialized virtual machine running on a fault-tolerant quantum computer, capable of performing cryptographic analysis on the quarantined host's traffic to identify novel threats that are computationally infeasible to detect with classical computers. The remediation process involves transmitting a quantum key distribution (QKD) secured patch to the host.

Mermaid.js Diagram:

sequenceDiagram
    participant Host
    participant CryoSwitch
    participant QuantumQuarantineServer
    Host->>CryoSwitch: Connection Request
    CryoSwitch->>QuantumQuarantineServer: Forward Request for Analysis
    QuantumQuarantineServer-->>CryoSwitch: Quarantine Decision (True/False)
    alt Quarantine Required
        CryoSwitch->>CryoSwitch: Allocate Power-Limited Wavelength to Host Port
        Host->>CryoSwitch: Outbound Traffic (e.g., to Mainframe)
        CryoSwitch->>QuantumQuarantineServer: Redirect traffic
        QuantumQuarantineServer->>Host: Remediation Instructions via QKD
    else Not Required
        CryoSwitch->>Host: Grant Full-Spectrum Access
    end

Derivative 2.2: Massive-Scale IoT Swarm Quarantine

Enabling Description: This application addresses a swarm of millions of low-power, ephemeral IoT devices (e.g., environmental sensors). A central mesh network controller receives connection requests. The "determination" is based on the collective behavior of a device's local cluster. If the aggregate data flow from a cluster of 1,000 devices deviates from a predicted model by more than a set threshold (e.g., 5 standard deviations), the entire cluster is flagged for quarantine. "Limited access" for the swarm is achieved by instructing the mesh network to refuse to route their traffic packets, except for packets directed to a specific remediation gateway that can push a signed firmware update. Non-remediation traffic is not redirected; it is simply dropped with a "route unavailable" response sent to the source node, minimizing network overhead.

Mermaid.js Diagram:

stateDiagram-v2
    state "Normal Operation" as Normal
    state "Quarantined" as Quarantined
    state "Under Observation" as Observation

    [*] --> Normal
    Normal --> Observation: Aggregate data deviates > 3σ
    Observation --> Normal: Anomaly resolves within 60s
    Observation --> Quarantined: Anomaly persists or exceeds 5σ
    Quarantined --> Normal: Signed firmware update received
    Quarantined --> Quarantined: Attempts non-remediation traffic (packets dropped)
    Normal --> Normal: Data within expected bounds

3. Cross-Domain Application

Derivative 3.1: Aerospace - In-Flight Avionics Bus Isolation

Enabling Description: Within an aircraft's federated avionics architecture (e.g., ARINC 664), a central gateway monitors the health and data integrity of all Line-Replaceable Units (LRUs) on the network. If an LRU (e.g., a flight management system) begins transmitting data that violates the predetermined bus timing, checksum, or semantic rules, the gateway determines it must be quarantined. The "quarantine" action involves the gateway ceasing to forward packets from the faulty LRU to critical flight control systems. "Limited access" is provided by allowing the quarantined LRU to communicate only with the Onboard Maintenance System (OMS). The OMS acts as the quarantine server, logging the LRU's fault data and providing diagnostic routines, but preventing its corrupt data from affecting the autopilot or navigation systems.

Mermaid.js Diagram:

graph TD
    subgraph Aircraft Network
        A[Flight Management System (LRU)] -- ARINC 664 Packets --> B{Avionics Gateway};
        C[Flight Controls]
        D[Onboard Maintenance System (OMS)]
    end

    B -- Valid Data --> C;
    B -- Anomalous Data Detected --> E{Quarantine Decision};
    E -- Quarantine=True --> F[Isolate LRU];
    F -- Block Traffic --> C;
    F -- Allow Traffic --> D;
    A -- Non-Remediation Traffic --> B
    B -- Blocked --> C

Derivative 3.2: AgTech - Automated Irrigation Network Safety

Enabling Description: In a smart farm, hundreds of wireless soil moisture sensors and valve actuators form a network. A central irrigation controller receives connection requests from these devices. If a sensor reports a value outside of physical possibility (e.g., 110% moisture) or an actuator fails to confirm its state change within a time limit, the controller determines the device must be quarantined. "Limited access" allows the device to communicate only with a diagnostic hub for recalibration or battery checks. Any commands from the quarantined device to open other valves (non-remediation traffic) are redirected to the diagnostic hub, which logs the command as an anomaly but does not execute it, preventing catastrophic flooding or crop dehydration due to a single faulty node.

Mermaid.js Diagram:

sequenceDiagram
    participant Sensor
    participant IrrigationController
    participant DiagnosticHub
    participant OtherValves

    Sensor->>IrrigationController: Report Moisture (110%)
    IrrigationController->>IrrigationController: Determination: Value is anomalous
    IrrigationController->>Sensor: Quarantine Flag Set
    Sensor->>IrrigationController: Request to Open Valve B
    IrrigationController->>DiagnosticHub: Redirected Request from Quarantined Sensor
    DiagnosticHub->>DiagnosticHub: Log Anomaly
    IrrigationController-->>OtherValves: No command forwarded

4. Integration with Emerging Tech

Derivative 4.1: AI-Driven Predictive Quarantine

Enabling Description: The quarantine determination logic is replaced with a recurrent neural network (RNN) trained on months of baseline network traffic metadata. The RNN model is hosted on a dedicated inference server. When a host connects, its initial traffic patterns (protocol usage, packet sizes, destination entropy) are fed into the RNN. The model outputs a "probability of future compromise" score. If this score exceeds a predefined risk threshold (e.g., 0.95), the system preemptively quarantines the host, even before any malicious activity is detected. The quarantine server provides remediation by forcing the user through a multi-factor authentication challenge and a mandatory security awareness module.

Mermaid.js Diagram:

graph LR
    A[Host Connects] --> B[Capture Initial Traffic Metadata];
    B --> C[AI Inference Server (RNN Model)];
    C -- Metadata Vector --> D{Calculate 'Future Compromise' Score};
    D -- Score > 0.95 --> E[Quarantine Host];
    E --> F[Redirect to MFA & Training Server];
    D -- Score <= 0.95 --> G[Allow Full Access];

Derivative 4.2: Blockchain-Audited Quarantine Policy

Enabling Description: The network access control policy (defining conditions for quarantine) is encoded as a smart contract on a permissioned blockchain (e.g., Hyperledger Fabric). A network gateway acts as a blockchain client. When a host requests access, the gateway queries the smart contract with the host's credentials (e.g., a signed certificate). The smart contract code executes the determination logic. If quarantine is required, the gateway executes the quarantine and writes a new transaction to the blockchain, creating an immutable, non-repudiable audit log of the event (who, what, when, why). The "quarantine server" is a decentralized application (dApp) that allows an administrator to review the audit log and push policy updates via new smart contract deployments.

Mermaid.js Diagram:

sequenceDiagram
    participant Host
    participant Gateway
    participant Blockchain
    participant dAppAdmin

    Host->>Gateway: Connection Request with Certificate
    Gateway->>Blockchain: Query SmartContract.ShouldQuarantine(HostCert)
    Blockchain-->>Gateway: Return Quarantine=True
    Gateway->>Gateway: Enforce Limited Access for Host
    Gateway->>Blockchain: Execute SmartContract.LogQuarantineEvent(Host, Reason)
    dAppAdmin->>Blockchain: View Immutable Audit Log

5. The "Inverse" or Failure Mode

Derivative 5.1: Graceful Degradation Quarantine (Fail-Safe Access)

Enabling Description: This design prioritizes availability. If a host is determined to be quarantined, but the designated quarantine server is unreachable (e.g., due to network failure or DDoS attack), the system enters a "graceful degradation" mode instead of blocking the host completely. In this mode, the host is granted access to a highly restricted, isolated network segment with egress-only access to a predefined list of external cloud services (e.g., office productivity suites, CRMs). All peer-to-peer traffic within the local network is blocked. This allows the user to remain productive with essential cloud tools while still preventing the potential spread of a lateral-moving threat on the internal network. The system logs all traffic for later analysis when the quarantine server is restored.

Mermaid.js Diagram:

stateDiagram-v2
    state "Determine Quarantine" as Check
    state "Full Access" as Full
    state "Fully Quarantined" as Quarantined
    state "Degraded Access" as Degraded

    [*] --> Check
    Check --> Full: Host is Clean
    Check --> Quarantined: Host is Dirty AND Quarantine Server is Reachable
    Check --> Degraded: Host is Dirty AND Quarantine Server is UNREACHABLE

    Quarantined --> Full: Remediation Complete
    Degraded --> Quarantined: Quarantine Server becomes Reachable
    Degraded: Egress-only to cloud apps
    Degraded: All internal P2P traffic blocked

Combination Prior Art Scenarios with Open-Source Standards

Combination with STIX/TAXII for Threat-Intel-Based Quarantine:
- Enabling Description: A network gateway subscribes to a threat intelligence feed from a TAXII server, receiving threat indicators in the STIX 2.1 format. The "determination of whether the host is required to be quarantined" is made by matching outbound connection requests from the host against STIX indicator objects from the feed. For example, if a host attempts a DNS lookup for a domain name matching an indicator of type domain-name associated with a known command-and-control server, the gateway immediately quarantines the host. The "quarantine server" provides the user with the specific STIX report that triggered the quarantine, offering transparency and context for the remediation.
Combination with RADIUS for Dynamic VLAN-Based Quarantine:
- Enabling Description: A host connects to a network port configured for 802.1X authentication. The network switch forwards the host's credentials to a FreeRADIUS server. The FreeRADIUS server, in addition to checking credentials, queries an external asset management database to determine the host's patch level. If the host is missing critical patches, the RADIUS server's "determination" is to return a Tunnel-Private-Group-ID attribute in its Access-Accept message. The switch interprets this attribute as a VLAN ID for the designated quarantine network. All non-remediation traffic is thus isolated at Layer 2. The quarantine server is a remediation portal, and once the host is patched, it must re-authenticate, at which point the RADIUS server will return a different VLAN ID for production access.
Combination with Prometheus/Alertmanager for Behavior-Based Quarantine:
- Enabling Description: Network traffic flow data is exported (e.g., via NetFlow/sFlow) to a Prometheus time-series database. A set of alerting rules in Prometheus monitors host behavior, such as rate(outbound_connections[5m]) > 100 or increase(dns_queries_to_rare_tlds[10m]) > 50. If a rule triggers, Prometheus sends an alert to Alertmanager. Alertmanager is configured with a webhook receiver that translates the alert into an API call to the network's SDN (Software-Defined Networking) controller. This API call serves as the "determination" to quarantine. The SDN controller then pushes a new flow rule to the relevant switch, redirecting the offending host's traffic (identified by its IP address in the alert payload) to the quarantine server.