Abstract: A source application executed within a source device may packetize and send source data over a link to a destination application executed within a destination device. In various embodiments, clock recovery processes are performed in conjunction with the destination application in order to synchronize the rates of source data production and consumption (e.g., playback). To facilitate the clock recovery process, a transport delay is calculated based on the difference between a source MAC-layer timestamp and a destination MAC-layer timestamp that envelop portions of the link that include variable delay elements. The transport delay is used by the clock recovery process to adjust a source application-layer timestamp, in one embodiment. In another embodiment, the transport delay is used by the destination device to impart a fixed cumulative transport delay on the source data before it is delivered to the destination application.

Abstract: A method may include sampling a receive frequency at which information received over a communication link is played. The method may also include sampling a system frequency related to the communication link and computing a first value based on the sampled receive frequency and the sampled system frequency. A second value may be received via the communication link. The receive frequency may be adjusted based on the first value and the second value.

Abstract: Machine-readable media, methods, and apparatus that time stamp events. In one embodiment, a time-stamping circuit may detect events of interest such as interrupt signals, arbitration signals, etc. In response to detecting such an event, the time-stamping circuit may store a time stamp for the event. A requester such as a processor may later request the time-stamping circuit for the time stamp of the event. The requester may then adjust a processing rate associated with the generation of such events based upon the retrieved time stamps.

Abstract: The present invention processes cable modem functions on a host computer. The cable modem receives hardware specific modem functions and transfers these functions to the host computer. An abstraction layer in the host computer receives the functions and converts the functions to/from hardware specific functions. The abstraction layer may be a DOCSIS abstraction layer. A firmware emulator (firmulator) then receives and processes the modem functions. The firmware emulator includes a plurality of state machines and networking protocol agents.

Abstract: A system and method of end-to-end clock recovery for media streaming. The method including inspecting a data packet sent by an application to determine a protocol type of the data packet and a location of a timestamp field in the data packet. If the data packet matches a pre-determined protocol type, a new timestamp is generated and inserted into the timestamp field of the packet in real-time in place of an original, possibly less reliable timestamp. The new timestamp accurately defines the time of transmission of the data packet. The data packet is transmitted over a network to a receiver. A receiver receiving the data packet, inspects the received data packet to determine whether the received data packet matches an identification criterion. If the received data packet matches the identification criterion, the receiver generates a local timestamp in real-time and processes the local timestamp and the new timestamp from the received packet to determine an error signal.

Abstract: A configuration file is provided to a communication device. Identification information associated with the communication device is received and configuration information is retrieved from a database based on the identification information. A configuration file is generated from the configuration information and provided to the communication device.

Abstract: A secure register in a cable modem is accessed only if properly encrypted data is received. The properly encrypted data is encrypted with a private key known only to a cable modem termination station. The data is decrypted with the public key stored in the cable modem. If the data and digital signature match, then the result of a hash function verifies that the data write is authorized. Configuration data, such as bandwidth data can be written only to the protected register in the cable modem, only if the data matches. Otherwise, the writing is prohibited. The method allows to securely access registers in electronic device remotely, using insecure communication media or channel. The method can be used to restrict access to critical data in registers or memory elements of a device, including ASICs, Flash and EEPROM memory components, to only positively authenticated sources of data.

Abstract: An enhanced residential gateway and associated methods is generally described. In accordance with one example embodiment of the invention, a method is presented comprising receiving a packet for transmission to a wide area network (WAN) from one of a plurality of coupled clients, analyzing at least a subset of content of the received packet to identify one or more characteristics of the received packet, and selectively modifying the received packet in accordance with one or more routing parameters from a routing parameters database based, at least in part, on the identified one or more characteristics of the received packet.

Abstract: A method is presented comprising receiving a data stream comprising timestamp information into a buffer, wherein the received data stream includes gaps, and generating an equalized reference clock from the received data stream by removing the gaps to facilitate equalized processing of the timestamp information received in a non-equalized data stream.

Abstract: Disclosed are a system and method of processing upstream bandwidth allocation messages in a downstream management message received at a client termination device. Bandwidth allocation elements based upon selected ones of the bandwidth allocation messages are stored in a data buffer. The stored bandwidth allocation elements may be accessed from the buffer in response to a validation of a cyclic redundancy code in the downstream management message.

Abstract: A system of managing security in a cable modem. Rules are defined enabling a host migrated cable modem to maintain security at specified times. The security is maintained by writing encryption keys to a register only when they are detected as being received in an authorized way. When the decryption keys have been received in an unauthorized way, then they can be received, but not used for decryption purposes. The register in includes a write enable function which enables writing the keys associated with a specified service ID. The register also includes a key destruction function.

Abstract: The present invention is a versatile time division multiple access (“TDMA”) slot allocation unit. In one embodiment, the versatile TDMA slot allocation unit includes a slot counter configured to provide an address representative of a time slot and a slot descriptor table that contains one or more slot descriptors each of which describes an action that may be performed within the time slot. The slot descriptor table is configured to receive the address and provide the slot descriptor pointed to by the address. In addition, the TDMA slot allocation unit includes a slot descriptor decoder configured to decode the slot descriptor and provide one or more signals.

Abstract: A data synchronization unit provides Time Division Multiple Access (TDMA) synchronization for a headend. The headend includes a network data source and transmits a plurality of data streams on a transmission medium. Included in the plurality of data streams is a first timing information element packet (TIE) generated by the network data source. The plurality of data streams are multiplexed by a multiplexer into a combined data stream. The data synchronization unit extracts the first timing packet from the combined data stream. The data synchronization unit then generates a second timing packet that compensates for a time delay of the multiplexer and inserts the second timing packet into the combined data stream in place of the first timing packet.