# US 2013/0155899 A1 · Method and Apparatus for Providing Conditional Access Based on Channel Characteristics > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0155899 A1 - Document ID: US20130155899A1 - Status: Published application - Kind: A1 - Application number: 13/328,721 - Filed: 2011-12-16 - Published: 2013-06-20 - Earliest claimed: 2011-12-16 - Assignees: MaxLinear, Inc. - Inventors: Timothy Gallagher - Web page: https://patentgrep.com/patent/US20130155899A1 ## CPC - H04L 63/0428: {wherein the data content is protected, e.g. by encrypting or encapsulating the payload} - G06F 21/00: Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity - G06F 21/105: {Arrangements for software license management or administration, e.g. for managing licenses at corporate level} - H04L 9/0819: {Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s) (network architectures or network communication protocols for key distribution in a packet data network H04L63/062)} - H04L 9/0861: {Generation of secret information including derivation or calculation of cryptographic keys or passwords} - H04L 9/0877: {using additional device, e.g. trusted platform module [TPM], smartcard, USB or hardware security module [HSM]} - H04L 9/3226: {using a predetermined code, e.g. password, passphrase or PIN (network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network H04L63/083)} - H04L 63/06: {for supporting key management in a packet data network (cryptographic mechanisms or cryptographic arrangements for key management H04L9/08)} - H04L 63/10: {for controlling access to devices or network resources} - G06F 21/107: {License processing; Key processing} - H04K 1/00: Secret communication - H04K 1/02: by adding a second signal to make the desired signal unintelligible - H04L 9/08: Key distribution {or management, e.g. generation, sharing or updating, of cryptographic keys or passwords (network architectures or network communication protocols for supporting key management in a packet data network H04L63/06)} - H04L 9/3006: {underlying computational problems or public-key parameters} - H04L 2209/24: Key scheduling, i.e. generating round keys or sub-keys for block encryption - H04L 2209/603: Digital right managament [DRM] - H04L 2463/101: applying security measures for digital rights management - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H04K: SECRET COMMUNICATION; JAMMING OF COMMUNICATION ## Abstract A first network device may discover one or more values of one or more parameters corresponding to a plurality of links and/or devices of the network. The first network device may compare the discovered one or more values of the one or more parameters to an expected one or more values of the one or more parameters. The first network device may determine whether to transmit data onto a network path between the first device and one of the plurality of devices based on a result of the comparison, wherein at least one of the plurality of links and/or devices are not part of the network path. The first network device may be operable to utilize the discovered parameter values to generate a security key which may be utilized to encrypt and/or scramble content prior to transmitting the content onto the network. ## Claims ### Claim 1 A system comprising: one or more circuits for use in a first network device of a network, said one or more circuits being operable to: discover one or more values of one or more parameters corresponding to a plurality of links and/or a plurality of devices of said network; and compare said discovered one or more values of said one or more parameters to an expected one or more values of said one or more parameters; and determine whether to transmit data onto a network path between said first network device and one of said plurality of devices based on a result of said comparison, wherein at least one of said plurality of links and/or plurality of devices are not part of said network path. ### Claim 2 (depends on 1) The system of claim 1, wherein said one or more parameters comprise one or more of: a length of one or more of said plurality of links; a phase response of one or more of said plurality of links; a frequency response of one or more of said plurality of links; a clock frequency offset between two of said plurality of devices; a clock phase offset between two of said plurality of devices; and a clock time offset between two of said plurality of devices. ### Claim 3 (depends on 1) The system of claim 1, wherein said one or more parameters comprise a plurality of modulation profiles utilized by one or more of said plurality of devices. ### Claim 4 (depends on 1) The system of claim 1, wherein said one or more parameters comprise an amount of time required for a particular packet to be communicated, via said network, from said first network device to a particular one of said plurality of devices. ### Claim 5 (depends on 1) The system of claim 1, wherein said one or more parameters comprise an amount of time between said first network device transmitting a request and receiving a corresponding response from one or more of said plurality of devices. ### Claim 6 (depends on 1) The system of claim 1, wherein said first network device is an Internet Protocol low noise block downconverter (IPLNB) that is collocated with a satellite dish. ### Claim 7 A system comprising: one or more circuits for use in a first network device of a network, said one or more circuits being operable to: discover one or more values of one or more parameters corresponding to a plurality of links and/or a plurality of devices of said network; generate one or more security keys utilizing said discovered one or more values; encrypt data utilizing said one or more security keys; and transmit said encrypted data onto a network path between said first network device and one of said plurality of devices, wherein at least one of said plurality of links and/or plurality of devices are not part of said network path. ### Claim 8 (depends on 7) The system of claim 7, wherein said one or more parameters comprise one or more of: a length of one or more of said plurality of links; a phase response of one or more of said plurality of links; a frequency response of one or more of said plurality of links; a clock frequency offset between two of said plurality of devices; a clock phase offset between two of said plurality of devices; and a clock time offset between two of said plurality of devices. ### Claim 9 (depends on 7) The system of claim 7, wherein said one or more parameters comprise a plurality of modulation profiles utilized by one or more of said plurality of devices. ### Claim 10 (depends on 7) The system of claim 7, wherein said one or more parameters comprise an amount of time required for a particular packet to be communicated, via said network, from said first network device to a particular one of said plurality of devices. ### Claim 11 (depends on 7) The system of claim 7, wherein said one or more parameters comprise an amount of time between said first network device transmitting a request and receiving a corresponding response from one or more of said plurality of devices. ### Claim 12 A system comprising: one or more circuits for use in a first network device of a network, said one or more circuits being operable to: receive encrypted data; discover one or more values of one or more parameters corresponding to a plurality of links and/or a plurality of devices of said network; generate one or more security keys utilizing said discovered one or more values; and decrypt said received encrypted data utilizing said one or more security keys. ### Claim 13 (depends on 12) The system of claim 12, wherein said one or more parameters comprise one or more of: a length of one or more of said plurality of links; a phase response of one or more of said plurality of links; a frequency response of one or more of said plurality of links; a clock frequency offset between two of said plurality of devices; a clock phase offset between two of said plurality of devices; and a clock time offset between two of said plurality of devices. ### Claim 14 (depends on 12) The system of claim 12, wherein said one or more parameters comprise a plurality of modulation profiles utilized by one or more of said plurality of devices. ### Claim 15 (depends on 12) The system of claim 12, wherein said one or more parameters comprise an amount of time required for a particular packet to be communicated, via said network, from said first network device to a particular one of said plurality of devices. ### Claim 16 (depends on 12) The system of claim 12, wherein said one or more parameters comprise an amount of time between said first network device transmitting a request and receiving a corresponding response from one or more of said plurality of network devices. ### Claim 17 A system comprising: a network coordinator of a multimedia over coax alliance (MoCA) network, said network coordinator being coupled to a plurality of network devices, and said network coordinator being operable to: upon one of said plurality of network devices requesting access to said MoCA network, discover one or more values of one or more parameters of said MoCA network; generate a network fingerprint utilizing said discovered one or more values; compare said generated network fingerprint to a known-valid network fingerprint for said MoCA network; accept said request if said generated network fingerprint matches said known-valid network fingerprint; and deny said request if said generated network fingerprint does not match said known-valid network fingerprint. ### Claim 18 (depends on 17) The system of claim 17, wherein said one or more parameters comprise one or more of: a length of one or more of said plurality of links; a phase response of one or more of said plurality of links; a frequency response of one or more of said plurality of links; a clock frequency offset between two of said plurality of devices; a clock phase offset between two of said plurality of devices; and a clock time offset between two of said plurality of devices. ### Claim 19 (depends on 17) The system of claim 17, wherein said one or more parameters comprise a plurality of modulation profiles utilized by one or more of said plurality of devices. ### Claim 20 (depends on 17) The network coordinator of claim 17, wherein said one or more parameters comprise an amount of time between said first network device transmitting a request and receiving a corresponding response from one or more of said plurality of network? devices.