Abstract: Disclosed embodiments relate to a Hierarchical Do-Dag based RPL (H-DOC) network configuration where the network address of each node corresponds to its location within the hierarchical network. Network addresses are initialized hierarchically. Candidate patent nodes signal availability. Candidate child nodes respond to a selected candidate parent node with a temporary address. The selected candidate parent node acknowledges selection and communicates a hierarchical address for the child node in a transmission to the temporary address. The child node changes its address to the hierarchical address from the parent node. When a node switches parent nodes, it signals the old parent node to deallocate it as a child node, and then signals a selected candidate parent node with a temporary address.

Abstract: A system and method for enhanced channel hopping sequence is described. A pseudo random channel hopping sequence is redistributed using certain system specific parameters for separating adjacent transmission channels within a predetermined number of consecutive transmission channel numbers in the random channel hopping sequence to improve inter-channel interference between adjacent transmission channels.

Abstract: An algorithm for the promotion of terminal nodes to switch nodes in a PLC network reduces overall network overhead and collisions, while ensuring the appropriate selection of a switch node and minimizing the number of levels in a PLC network. It also ensures that the terminal nodes with appropriate signal-to-noise ratios (SNRs) are promoted. It is desirable to have a network with fewer levels. The disclosed approach favors the nodes that are closer to the DC to promote them as switch nodes. This is achieved by waiting for a smaller number of PNPDUs for a node that is closer to the DC in comparison to a node that is farther away from the DC.

Abstract: Systems and methods for efficiently allocating beacon slot among multiple nodes on multiple levels within a power line communication network are described. In various implementations, these systems and methods may be applicable to Power Line Communications (PLC). For example, a method may include performing, by a communications device, assigning beacon transmission times to nodes within the communication device's network. The assigned beacon transmission times comprise a beacon slot and frame pattern. The beacon slot and frame pattern ensure that each node does not transmit a beacon in a beacon slot that is adjacent to a beacon slot assigned to a parent or child node. A beacon transmission slot is reserved for a base node in every frame. The frames may be organized into thirty-two-frame superframes, wherein each frame comprises a base node beacon slot and four switch node beacon slots.

Abstract: Embodiments of methods and systems for supporting coexistence of multiple technologies in a Power Line Communication (PLC) network are disclosed. A long coexistence preamble sequence may be transmitted by a device that has been forced to back off the PLC channel multiple times. The long coexistence sequence provides a way for the device to request channel access from devices on the channel using other technology. The device may transmit a data packet after transmitting the long coexistence preamble sequence. A network duty cycle time may also be defined as a maximum allowed duration for nodes of the same network to access the channel. When the network duty cycle time occurs, all nodes will back off the channel for a duty cycle extended inter frame space before transmitting again. The long coexistence preamble sequence and the network duty cycle time may be used together.

Abstract: A radio communications device includes a RTC configured to run even during sleep for receiving from a coordinator node (CN) in an asynchronous channel hopping WPAN an asynchronous hopping sequence (AHS) frame that includes the CN's hopping sequence. A processor implements a stored sleepy device operation in asynchronous channel hopping networks algorithm. The algorithm is for determining a time stamp for the AHS frame and the CN's initial timing position within the hopping sequence, storing the time stamp, going to sleep and upon waking up changing a frequency band of its receive (Rx) channel to an updated fixed channel. A data request command frame is transmitted by the device on the CN's listening channel that is calculated from the CN's hopping sequence, time stamp, CN's initial timing position and current time, and the device receives an ACK frame transmitted by the CN at the updated fixed channel of Rx operation.

Abstract: A method of channel access for a radio device in an asynchronous channel hopping wireless network. A backoff time is set from an Interference Avoidance Delay plus a random backoff time for transmissions from the radio device. For initial frame transmissions, an initial value for a number of backoffs (nb) and initial number of preamble detection backoffs (npdb) is set. After waiting for expiring of the initial backoff time and provided a current npdb_value<a predetermined maximum npdb value, a first CCA is performed on the radio device's receive (Rx) channel, and a value for npdb is incremented following a failure. A second CCA is performed on a target radio device's Rx channel, wherein a value for nb is incremented following a failure. Provided a not busy is determined in the second CCA the radio device transmits a frame on the target radio device's Rx channel.

Abstract: This invention is an improvement of a Hierarchical Do-Dag based RPL (H-DOC) network configuration where the network address of each node corresponds to its location within the hierarchical network. Network addresses are initialized hierarchically. Candidate patent nodes signal availability. Candidate child nodes respond to a selected candidate parent node with a temporary address. The selected candidate parent node acknowledges selection and communicates a hierarchical address for the child node in a transmission to the temporary address. The child node changes its address to the hierarchical address from the parent node. When a node switches parent nodes, it signals the old parent node to deallocate it as a child node, and then signals a selected candidate parent node with a temporary address.

Abstract: A radio communications device includes a RTC configured to run even during sleep for receiving from a coordinator node (CN) in an asynchronous channel hopping WPAN an asynchronous hopping sequence (AHS) frame that includes the CN's hopping sequence. A processor implements a stored sleepy device operation in asynchronous channel hopping networks algorithm. The algorithm is for determining a time stamp for the AHS frame and the CN's initial timing position within the hopping sequence, storing the time stamp, going to sleep and upon waking up changing a frequency band of its receive (Rx) channel to an updated fixed channel. A data request command frame is transmitted by the device on the CN's listening channel that is calculated from the CN's hopping sequence, time stamp, CN's initial timing position and current time, and the device receives an ACK frame transmitted by the CN at the updated fixed channel of Rx operation.

Abstract: Embodiments of methods and systems for supporting coexistence of multiple technologies in a Power Line Communication (PLC) network are disclosed. A long coexistence preamble sequence may be transmitted by a device that has been forced to back off the PLC channel multiple times. The long coexistence sequence provides a way for the device to request channel access from devices on the channel using other technology. The device may transmit a data packet after transmitting the long coexistence preamble sequence. A network duty cycle time may also be defined as a maximum allowed duration for nodes of the same network to access the channel. When the network duty cycle time occurs, all nodes will back off the channel for a duty cycle extended inter frame space before transmitting again. The long coexistence preamble sequence and the network duty cycle time may be used together.

Abstract: Authentication of a networked device with limited computational resources for secure communications over a network. Authentication of the device begins with the supplicant node transmitting a signed digital certificate with its authentication credentials to a proxy node. Upon verifying the certificate, the proxy node then authenticates the supplicant's credentials with an authentication server accessible over the network, acting as a proxy for the supplicant node. Typically, this verification includes decryption according to a public/private key scheme. Upon successful authentication, the authentication server creates a session key for the supplicant node and communicates it to the proxy node. The proxy node encrypts the session key with a symmetric key, and transmits the encrypted session key to the supplicant node which, after decryption, uses the session key for secure communications. In some embodiments, the authentication server encrypts the session key with the symmetric key.

Abstract: In a disclosed embodiment, a method for communication in a network includes receiving, at a first device registered to the network, a physical layer (PHY) frame that includes a PHY header and a MAC header. The PHY frame may further include a MAC payload. The PHY header includes a destination address field. The method further includes comparing a network address of the first device to the destination address field to determine whether the destination address field stores a value having the same number of bits as the network address. When the comparison indicates that the value stored by the destination address field does not have the same number of bits as the network address, the method skips decoding the MAC header and the MAC payload.

Abstract: A method of channel access for a radio device in an asynchronous channel hopping wireless network includes a channel hopping coordinator first radio device transmitting its receive (Rx) channel hopping sequence to a fixed or semi-channel hopping sleepy radio device. The sleepy radio device tracks the first radio device's Rx channel using the channel hopping sequence and transmits a poll frame exclusive of a unicast schedule information element (US-IE) on the first radio device's current Rx channel to the first radio device. The sleepy radio device moves to an updated Rx channel that is a function of the current Rx channel. The first radio device receives the poll frame and then computes the updated Rx channel as the function of the current Rx channel. After the computing, the first radio device transmits a data frame to the sleepy radio device on the updated Rx channel.

Abstract: Disclosed embodiments include a network device having a split network stack that includes a physical (PHY) layer associated with first and second media access control (MAC) protocol sublayers, a processing device, and memory storing instructions that, when executed by the processing device, cause the processing device to select a route through the split network stack that includes one of the first and second MAC protocol sublayers but not the other one of the first and second MAC protocol sublayers.

Abstract: Authentication of a networked device with limited computational resources for secure communications over a network. Authentication of the device begins with the supplicant node transmitting a signed digital certificate with its authentication credentials to a proxy node. Upon verifying the certificate, the proxy node then authenticates the supplicant's credentials with an authentication server accessible over the network, acting as a proxy for the supplicant node. Typically, this verification includes decryption according to a public/private key scheme. Upon successful authentication, the authentication server creates a session key for the supplicant node and communicates it to the proxy node. The proxy node encrypts the session key with a symmetric key, and transmits the encrypted session key to the supplicant node which, after decryption, uses the session key for secure communications. In some embodiments, the authentication server encrypts the session key with the symmetric key.

Abstract: A method of channel access for a radio device in an asynchronous channel hopping wireless network includes a channel hopping coordinator first radio device transmitting its receive (Rx) channel hopping sequence to a fixed or semi-channel hopping sleepy radio device. The sleepy radio device tracks the first radio device's Rx channel using the channel hopping sequence and transmits a poll frame exclusive of a unicast schedule information element (US-IE) on the first radio device's current Rx channel to the first radio device. The sleepy radio device moves to an updated Rx channel that is a function of the current Rx channel. The first radio device receives the poll frame and then computes the updated Rx channel as the function of the current Rx channel. After the computing, the first radio device transmits a data frame to the sleepy radio device on the updated Rx channel.

Abstract: A method of channel access for a radio device in an asynchronous channel hopping wireless network. A backoff time is set from an Interference Avoidance Delay plus a random backoff time for transmissions from the radio device. For initial frame transmissions, an initial value for a number of backoffs (nb) and initial number of preamble detection backoffs (npdb) is set. After waiting for expiring of the initial backoff time and provided a current npdb_value<a predetermined maximum npdb value, a first CCA is performed on the radio device's receive (Rx) channel, and a value for npdb is incremented following a failure. A second CCA is performed on a target radio device's Rx channel, wherein a value for nb is incremented following a failure. Provided a not busy is determined in the second CCA the radio device transmits a frame on the target radio device's Rx channel.

Abstract: In a method for communicating with a plurality of devices using different communication protocols, a signal is received at a transceiver device from a neighbor device via a physical layer of a communication media. At a first time the signal contains a header frame from a first device conforming to a first communication protocol and at another time the signal contains a header frame from a second device conforming to a second communication protocol. The transceiver determines which of the different communication protocols is being used by each of the plurality of devices. The transceiver may then process inbound payload data using the indentified protocol type. Data frames are transmitted to the first device using the first communication protocol and data frames are transmitted to the second device using the second communication protocol.

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: A communication system and method includes receiving payload data of first and second media access control (MAC) frames. A MAC-level protocol is identified in response to the indication of the selected network for each of the first and second MAC frames. The payload data of the first and second MAC frames is transmitted and/or received across respective networks transmitted using, for example, power line communications signals over a common communications medium. The common communications medium is operable for carrying signals of a plurality of networks.