Abstract: Systems and methods for designing, using, and/or implementing media access control (MAC) protocols with subbanding are described. In some embodiments, a method may include receiving a beacon packet during one of a plurality of beacon slots of a superframe, each beacon slot corresponding to one of a plurality of different downlink subbands. The method may also include identifying, based on the received beacon packet, contention access periods following the beacon slots, each of the contention access periods corresponding to one of a plurality of different uplink subbands. The method may further include transmitting an information packet over each of the plurality of uplink subbands during the contention access periods. Then, the method may include receiving, during a guaranteed time slot following the contention access periods, an indication of a selected one of the plurality of uplink subbands to be used in a subsequent communications.

Abstract: Embodiments of the invention provide systems and methods for a cipher then segment approach in a Power Line Communication (PLC). A node or device generates frames to be transmitted to a destination node in the PLC network. A processor in the node is configured to generate a data payload comprising data to be sent to the destination node. The processor divides the data payload into two or more payload segments and encrypts the payload segments. The processor creates a frame for each of the encrypted payload segments, wherein each frame comprises a message integrity code. The processor creates a segment identifier for each frame using the message integrity code and an authentication key that is shared with the destination PLC node. The segment identifier is added to each frame.

Abstract: Embodiments of methods and systems for overlapping priority contention windows in G3-PLC networks are presented. In one embodiment, a Normal Priority Contention Window (NPCW) is allowed to overlap with a High Priority Contention Window (HPCW). The minimum contention window for the normal priority frames (i.e., NPCW) is equal to or longer than the contention window for high priority frames (i.e., HPCW). By making the NPCW longer than the HPCW, the high priority frames will have a better chance than normal priority frames to get access to the channel on transmission reattempts.

Abstract: Segmented frames of data may be transmitted from a transmitting device using conflict free slots (CFS) within a carrier sense multiple access with collision avoidance (CSMA/CA) protocol on a noisy media. At a receiver, a segmented frame of data is received. The data is represented by a plurality of tones. If requested by the transmitter, a tone map response command is prepared that specifies a set of optimized tone map parameters by analyzing the received frame of data. Any previously determined tone map response commands to the transmitting device are deleted. A sequence of frame segments may be received in conflict free slots, but only one tone map response is transmitted to the transmitting device after receiving the entire sequence of frame segments.

Abstract: Systems and methods for designing, using, and/or implementing hybrid communication networks are described. In various embodiments, these systems and methods may be applicable to power line communications (PLC). For example, one or more of the techniques disclosed herein may include methods to coordinate medium-to-low voltage (MV-LV) and low-to-low voltage (LV-LV) PLC networks when the MV-LV network operates in a frequency subband mode and the LV-LV network operates in wideband mode (i.e., hybrid communications). In some cases, MV routers and LV routers may have different profiles. For instance, MV-LV communications may be performed using MAC superframe structures, and first-level LV to lower-level LV communications may take place using a beacon mode. Lower layer LV nodes may communicate using non-beacon modes. Also, initial scanning procedures may encourage first-to-second-level LV device communications rather than MV-to-first-level LV connections.

Abstract: A physical layer (PHY) data frame for use in conjunction with processor in a node, processor coupled to a program memory for storing a sequence of operating instructions. The frame has a preamble, PHY header, a MAC header and a MAC payload. The PHY header includes a destination address field having a destination address therein. The destination address is used by the processor to determine match with the node address.

Abstract: A method of powerline communications in a powerline communications (PLC) network including a first PLC device and at least a second PLC device. The first PLC device transmits a data frame to the second node over a PLC channel. The second PLC device has a data buffer for storing received information. The second PLC device runs a flow control algorithm which determines a current congestion condition or a projected congestion condition of the data buffer based on at least one congestion parameter. The current congestion condition and projected congestion condition include nearly congested and fully congested. When the current or projected congestion condition is either nearly congested or fully congested, the second PLC device transmits a BUSY including frame over the PLC channel to at least the first PLC device. The first PLC device defers transmitting of any frames to the second PLC device for a congestion clearing wait time.

Abstract: Systems and methods for designing, using, and/or implementing non-beacon network communications using frequency subbands are described. In various implementations, these systems and methods may be applicable to Power Line Communications (PLC). For example, a method may include transmitting a beacon request message over a given one of a plurality of frequency subbands, receiving a plurality of beacons in response to having transmitted the beacon request message, each of the plurality of beacons received over a respective one of the plurality of frequency subbands, and calculating a downlink quality report based, at least in part, upon the received beacons. The method may also include transmitting the downlink quality report over each of the plurality of frequency subbands and receiving a subband allocation command in response to having transmitted the downlink quality report, the subband allocation command indicating a downlink subband assignment and an uplink subband assignment.

Abstract: Systems and methods for designing, using, and/or implementing communications in beacon-enabled networks are described. In various implementations, these systems and methods may be applicable to power line communications (PLC). For example, a method may include identifying one of a plurality of orthogonal superframes. The identified superframe may include beacon slots and contention access period (CAP) slots. The beacon slots may follow a sequence of two or more frequency subbands, and the CAP slots may follow the same sequence of two or more frequency subbands. Also, the sequence of two or more frequency subbands may be distinct from other sequences of two or more frequency subbands followed by other beacon slots and CAP slots within others of the plurality of available superframes. The method may then include communicating with another device using the identified superframe.

Abstract: A method of powerline communications including a first node and at least a second node on a powerline communications (PLC) channel in a PLC network. The first node sends a physical layer (PHY) data frame on the PLC channel including a preamble, a PHY header, a MAC header and a MAC payload. The MAC header includes a Cyclic Redundancy Check (CRC) field (MH-CRC field). The second node receives the data frame, parses the MAC header to reach the MH-CRC field, and performs CRC verification using the MH-CRC field to verify the MAC header. If the CRC verification is successful, (i) the second node parses another portion of the MAC header to identify a destination address of the data frame and (ii) to determine whether the data frame is intended for the second node from the destination address.

Abstract: A method of powerline communications (PLC) includes compiling a data frame for physical layer (PHY) by a first communications device at a first communications node on a powerline of a PLC network. The data frame includes a single tone PHY header portion and a data payload portion in a set of tones including at least one tone having a frequency different from a frequency of the single tone. The PHY header portion includes tone mask identification information identifying the set of tones. The first communications device transmits the data frame over the powerline to a second communications device at a second communications node on the powerline. The second communications device receives the data frame, and decodes the data payload using the tone mask identification information in the PHY header portion.

Abstract: A method of network joining. A first service node (SN) of SNs in a multi-Personal Area Network including data concentrators (DCs) that communicate with a server over a common communications medium configures a beacon request frame (BRF) including a Media Access Control (MAC) header including a header information element (HIE) or a payload IE (PIE), and a MAC CRC footer. The BRF includes a unique address of a first DC corresponding to the first SN or an encrypted data sequence with a key. The first SN transmits the BRF over the common communications medium. Responsive to receiving the BRF, the first DC processes the BRF to identify the unique address or has the key and applies the key to decipher the encrypted BRF. The first DC transmits a beacon frame over the common communications medium, wherein others of the plurality of DCs do not transmit respective beacon frames.

Abstract: A method of network joining. A first service node (SN) of SNs in a multi-Personal Area Network including data concentrators (DCs) that communicate with a server over a common communications medium configures a beacon request frame (BRF) including a Media Access Control (MAC) header including a header information element (HIE) or a payload IE (PIE), and a MAC CRC footer. The BRF includes a unique address of a first DC corresponding to the first SN or an encrypted data sequence with a key. The first SN transmits the BRF over the common communications medium. Responsive to receiving the BRF, the first DC processes the BRF to identify the unique address or has the key and applies the key to decipher the encrypted BRF. The first DC transmits a beacon frame over the common communications medium, wherein others of the plurality of DCs do not transmit respective beacon frames.

Abstract: A method of powerline communications including a first node and at least a second node on a PLC channel in a PLC network. The first node sends a physical layer (PHY) data frame on the PLC channel including a preamble, PHY header, a MAC header and a MAC payload. The PHY header includes a destination address field having a destination address therein. The second node receives the data frame. The second node compares its network address to the destination address before decoding the MAC header and MAC payload, providing power savings by allowing the second node to not decode the MAC header or MAC payload if its network address does not match the destination address in the PHY header of the data frame.

Abstract: A method of powerline communications in a powerline communications (PLC) network including a first node and at least a second node. The first node transmits a data frame to the second node over a PLC channel. The second node has a data buffer for storing received information. The second node runs a flow control algorithm which determines a current congestion condition or a projected congestion condition of the data buffer based on at least one congestion parameter. The current congestion condition and projected congestion condition include nearly congested and fully congested. When the current or projected congestion condition is either nearly congested or fully congested, the second node transmits a BUSY including frame over the PLC channel to at least the first node. The first node defers transmitting of any frames to the second node for a congestion clearing wait time.

Abstract: Systems and methods for designing, using, and/or implementing hybrid communication networks are described. In various embodiments, these systems and methods may be applicable to power line communications (PLC). For example, one or more of the techniques disclosed herein may include methods to coordinate medium-to-low voltage (MV-LV) and low-to-low voltage (LV-LV) PLC networks when the MV-LV network operates in a frequency subband mode and the LV-LV network operates in wideband mode (i.e., hybrid communications). In some cases, MV routers and LV routers may have different profiles. For instance, MV-LV communications may be performed using MAC superframe structures, and first-level LV to lower-level LV communications may take place using a beacon mode. Lower layer LV nodes may communicate using non-beacon modes. Also, initial scanning procedures may encourage first-to-second-level LV device communications rather than MV-to-first-level LV connections.

Abstract: Systems and methods for designing, using, and/or implementing non-beacon network communications using frequency subbands are described. In various implementations, these systems and methods may be applicable to Power Line Communications (PLC). For example, a method may include transmitting a beacon request message over a given one of a plurality of frequency subbands, receiving a plurality of beacons in response to having transmitted the beacon request message, each of the plurality of beacons received over a respective one of the plurality of frequency subbands, and calculating a downlink quality report based, at least in part, upon the received beacons. The method may also include transmitting the downlink quality report over each of the plurality of frequency subbands and receiving a subband allocation command in response to having transmitted the downlink quality report, the subband allocation command indicating a downlink subband assignment and an uplink subband assignment.

Abstract: Transmission over a communication channel using carrier sense multiple access collision avoidance (CSMA/CA) may be performed by determining for each frame if the communication channel is busy after a backoff time proportional to a randomly generated number within a contention window (CW). When the channel is not busy, a frame of data may be transmitted. When the channel is busy, the device may periodically determine if the communication channel is busy after subsequent backoff times. The value of CW is adjusted for each subsequent backoff time using a fairness protocol, in which the value of CW is increased until the value of CW reaches a maximum CW value; and then the value of CW is held until a fairness number of backoff repetitions reaches a fairness threshold; then the value of CW is reduced incrementally until the value of CW reaches a minimum CW value.

Abstract: Method and apparatus for avoiding hidden node collisions in a communication network. A network communication device includes a packet transmitter. The packet transmitter is configured to subdivide a packet to be transmitted via a communication network into a plurality of segments based on the packet exceeding a predetermined maximum size, and to sequentially transmit the segments via the communication network. The packet transmitter is also configured to construct an acknowledgement packet responsive to reception of each segment of a packet received via the communication network. The acknowledgement packet includes a field indicating whether an additional segment of the packet is to be transmitted via the communication network. The packet transmitter is further configured to transmit the acknowledgement packet via the communication network.

Abstract: A method of communications in a network having plurality of nodes including a base node (BN) and a plurality of levels (i) each including at least one service node (SN). The number (Ni(t)) of SNs registered in each of a plurality of i are determined. The current Keep Alive timer out (KA_TO) value for a KA timer at the BN is dynamically adjusted to an updated KA_TO value based on Ni(t) and i. Dynamically adjusting KA_TO values reduces the KA message overhead the network compared to known KA_TO value implementations.