Abstract: Systems and methods for connecting new stations to a secure network. New stations can send connection requests to a headend device. The headend device can retrieve a device access key associated with the new station and can provide a network membership key to the new station based upon authentication of the new station using the device access key.

Abstract: Systems and methods for authorizing a customer premise equipment (CPE) device to join a network through a network termination unit (NTU). The CPE device can send an encrypted connection request, and an authorization server can decrypt the connection request and provide a network membership key (NMK) associated with the CPE device to the NTU. The authorization server can encrypt the NMK associated with the CPE device using a device access key (DAK) associated with the NTU.

Abstract: Communicating between stations in a network is described. A plurality of stations coordinate according to a distributed protocol to select a first station to transmit over a shared medium. The communication includes transmitting between the first station and a second station over the shared medium during a time period in which stations other than the first and second stations refrain from transmitting over the shared medium. The first station transmits information that grants permission to the second station to transmit during the time period.

Abstract: An access contention scheme having both multi-level priorities and a contention-free access indicator for use by a station in a network of stations. When a contention control indicator is detected for a contention period, a station having a frame to transmit determines from the contention control indicator if it is permitted to contend for access to the transmission medium during the contention period. The station determines if the contention control indicator indicates a contention-free access and, if the contention control information indicates a contention-free access, the station determines it a channel access priority level associated with the frame to be transmitted is higher than a channel access priority level associated with a last transmitted frame.

Abstract: Communicating over a network of communication stations includes monitoring for reception of an electromagnetic wave that has a power above a threshold and a frequency in a predetermined frequency interval, and selecting carrier frequencies for modulating information onto signals transmitted over the network. The carrier frequencies are selected based at least in part on whether an electromagnetic wave having a power above the threshold and a frequency in the frequency interval has been received in a predetermined time interval, and based at least in part on a demand by one or more stations in the network for capacity for communicating over the network.

Abstract: An access contention scheme having both multi-level priorities and a contention-free access indicator for use by a station in a network of stations. When a contention control indicator is detected for a contention period, a station having a frame to transmit determines from the contention control indicator if it is permitted to contend for access to the transmission medium during the contention period. The station determines if the contention control indicator indicates a contention-free access and, if the contention control information indicates a contention-free access, the station determines if a channel access priority level associated with the frame to be transmitted is higher than a channel access priority level associated with a last transmitted frame.

Abstract: A rate-adaptive mechanism for optimizing transmitter/receiver connections on a carrier-by-carrier basis for maximum date rate based on channel attributes for that connection and direction. Channel information is produced by a channel adaptation process based on channel characteristics and is stored in both transmitter and receiver as a channel map with an associated a channel map index for channel map look-up. The channel map index for a channel map used to modulate a payload of a frame is conveyed by transmitter to receiver in the frame so that the receiver is able to select the correct channel map for demodulation.

Abstract: A method of operating in a network in which a plurality of stations communicate over a shared medium. The method comprises transmitting a group of bits from a transmitting station to a receiving station, wherein the group of bits comprises information bits and error checking bits, and communicating additional bits from the transmitting station to the receiving station without transmitting the additional bits. Communicating the additional bits comprises, at the transmitting station, deriving the error checking bits from the additional bits using an error checking process; and at the receiving station, using the same or a related error checking process to process candidate bits known to the receiving station, and comparing the output of the error checking process to the error checking bits received from the transmitting station to determine if the candidate bits correspond to the additional bits.

Abstract: A method for establishing shared information is described. The method includes estimating characteristics of a communication channel between two nodes based on signals transmitted between the nodes. The method also includes transmitting a signal from the first node to the second node, the signal being modulated with a first data sequence according to a first estimated characteristic, and transmitting a signal from the second node to the first node, the signal being modulated with a second data sequence according to a second estimated characteristic. Shared information is formed at each of the first and second nodes based on at least a portion of the first data sequence and at least a portion of the second data sequence.

Abstract: A frame forwarding scheme for network stations operating in a shared medium data transmissions network. The frame forwarding scheme uses payload encapsulating delimiters and control information in the payload to enable a frame originating from a first station and intended for a second station to be forwarded to the second station by an intermediate station. The first station selects a station as an intermediate station for purposes of frame forwarding based on the data transmission quality or reliability to be achieved using that station as an intermediate station.

Abstract: A scheme for bounding latency of transmissions for QoS in network stations operating in shared medium access network. The length of segment burst transmissions are limited by allowing the segment burst transmission of a given priority to be interrupted by higher priority traffic. Restrictions are placed on frame length for transmissions of all priority levels or, alternatively, at all but the highest of the priority levels.

Abstract: A CSMA Media Access Control (MAC) scheme for supporting both centralized and distributed shared medium access control in a CSMA network. A master device exchanges connection control messages with a slave during using contention-oriented access to establish a connection and a session of periodic contention-free intervals. Once the session is established, the contention-free intervals alternate with contention-oriented intervals according to the timing parameters specified by the connection control messages.

Abstract: A method of operating in a network in which stations communicate over a shared medium is described. The method provides regularly repeated contention free intervals, CSMA communication during times outside the contention free intervals, and distributed control over the initiation and makeup of the contention free intervals to a plurality of stations so that any of the plurality of stations can independently initiate transmission within the contention free interval.

Abstract: A robust Media Access Control (MAC) scheme for network stations operating in an OFDM transmissions network. The MAC scheme uses robustly transmitted frame control information to ensure network synchronization (for media access) and convey channel access prioritization for QoS. Frame control information can occur in a frame before and after the frame's payload, or in a response.

Abstract: A scheme for configuring an FEC encoder (including an associated interleaver) for changing data channel characteristics. Channel information specifying a modulation mode and carriers capable of supporting the modulation mode for the data channel is received by a transmitting network node for use in a data transmission to a receiving network node. The received channel information is based on a prior data transmission to the receiving network node over the data channel. Configuration values are computed from the received channel information and an amount of data to be transmitted in a data transmission. The FEC encoder is configured to operate on the data transmission data amount according to the configuration information.

Abstract: A partial ARQ protocol for multicast and broadcast transmissions in network devices operating in a shared medium access network. To support the partial ARQ, a media access control (MAC) protocol uses robustly transmitted frame delimiters and a MAC management frame structure. In a multicast or broadcast frame with partial ARQ, a destination address field is set to that of a selected proxy device's address, and the address of the intended recipients (of group address of the intended recipients) is placed in an entry in the MAC management frame structure. The frame also contains a multicast flag set to indicate that the transmission is intended for more than one device and a value in the frame delimiters to indicate that a response is requested. Upon receipt of such a frame, the proxy device specified by the destination address field provides an appropriate response type on behalf of the group.

Abstract: A scheme for configuring an FEC encoder (including an associated interleaver) for changing data channel characteristics. Channel information specifying a modulation mode and carriers capable of supporting the modulation mode for the data channel is received by a transmitting network node for use in a data transmission to a receiving network node. The received channel information is based on a prior data transmission to the receiving network node over the data channel. Configuration values are computed from the received channel information and an amount of data to be transmitted in a data transmission. The FEC encoder is configured to operate on the data transmission data amount according to the configuration information.

Abstract: A scheme for identifying usable carriers for a particular modulation type and selecting, if possible, a modulation type for modulation of OFDM symbol block associated with data packets in a standard transmission mode based on data channel conditions. Channel estimation for an OFDM symbol block received by a receiving network node over a data channel during a packet transmission by a transmitting network node generates information indicative of noise events on symbols and carriers in the OFDM block, the generated information being related to modulation types available for the standard transmission mode, and determines from the generated information if at least one of the modulation types available for the standard transmission mode may be used for a next data transmission over the data channel by the transmitting network node using the standard transmission mode. One of the modulation types is selected if it is determined that at least one of the modulation types may be used.

Abstract: A scheme for configuring an FEC encoder (including an associated interleaver) for changing data channel characteristics. Channel information specifying a modulation mode and carriers capable of supporting the modulation mode for the data channel is received by a transmitting network node for use in a data transmission to a receiving network node. The received channel information is based on a prior data transmission to the receiving network node over the data channel. Configuration values are computed from the received channel information and an amount of data to be transmitted in a data transmission. The FEC encoder is configured to operate on the data transmission data amount according to the configuration information.

Abstract: An encoder/decoder scheme for robust transmission of PHY layer frame control information (to support medium access) in OFDM frames (or packets). The PHY layer frame control information to be modulated onto carriers in OFDM symbols is encoded using a product coding to form a product code block or matrix. The product coding is based on a shortened hamming code codeword set having properties of symmetry. Elements of the product code matrix are interleaved so that the elements are modulated onto the carriers of the symbols in diagonal groupings (across time and frequency) and with some degree of redundancy. The modulated elements are demodulated to produce soft decision values, which are de-interleaved to combine copies of the soft values for elements and re-order the soft values in the order of the elements prior to interleaving.