Abstract: Techniques are provided to improve the performance of wireless devices that serve wireless client devices in a wireless network in the presence of narrowband interference. The wireless device that serves wireless client devices in the wireless network receives energy in a plurality of channels of a frequency band. The received energy is analyzed for occurrence and type of interference in each channel. A quality metric is generated for each channel incorporating the occurrence and type of interference detected in the channel. For each channel, a bias value against selection of the channel is assigned based on whether narrowband interference is present in the channel. The bias value for each channel is applied to the quality metric for the channel to produce an adjusted quality metric for each channel. A channel is selected based on the adjusted quality metric for each of the plurality of channels.

Abstract: In an example embodiment, an apparatus selects radio channels based on persistent interference device information. The apparatus comprises a wireless transceiver operable to communicate over a plurality of channels and channel selection logic in communication with the wireless transceiver and operable to select a channel for the wireless transceiver. The channel selection logic is operable to acquire data representative of intensity, duration and rate of occurrence for at least one persistent interference device detected by the wireless transceiver operating on at least one of the plurality of channels. The channel selection logic is operable to select a channel for the wireless transceiver based on the data representative of intensity, duration and rate of occurrence for the at least one persistent interference device.

Abstract: Techniques are provided to determine channel assignments for wireless access point (AP) devices in a wireless local area network (WLAN). From each of a plurality of AP devices operating at least one of a plurality of channels in the WLAN, wireless activity data is received that represents activity in each channel associated with signals of devices operating in the WLAN and associated with signals and energy from devices that are not operating in the WLAN as detected by the AP devices by receiving radio frequency energy in each of the plurality of channels.

Abstract: In one embodiment, a device in a computer network monitors an alternating-current (AC) waveform of an electrical power source at the device, where the power source is part of a polyphase power source system. Once the device determines a particular phase of the polyphase power source system at the device, then the device joins a directed acyclic graph (DAG) specific to the particular phase. In another embodiment, a device detects a time of a zero crossing of the AC waveform, and may then determine a particular phase of the polyphase power source system at the device based on the time of the zero crossing relative to a corresponding location within a frequency hopping superframe of the computer network.

Abstract: In one embodiment, a sender in a frequency hopping wireless network classifies a message as a large message to be fragmented into a plurality of packets for transmission to a receiver, and in response, indicates to the receiver that the message is a large message to request use of an orthogonal frequency hopping sequence between the sender and receiver for the duration of the large message transmission, the orthogonal frequency hopping sequence orthogonal to a shared frequency hopping sequence of the wireless network. Thereafter, the sender transmits the large message to the receiver on the orthogonal frequency hopping sequence, and returns to the shared frequency hopping sequence upon completion. In another embodiment, the receiver receives the indication that a message is a large message (requesting use of the orthogonal frequency hopping sequence). If the receiver can comply, the large message is received on the orthogonal frequency hopping sequence.

Abstract: In one embodiment, a particular node in a primary DAG receives a distributed message from distributing nodes, and from this, deterministically selects a distributing node as a distributing parent in a secondary DAG from which distributed messages are to be received. The particular node may then inform the deterministically selected distributing parent that it is being used by the particular node as its distributing parent, and if the selected distributing parent is not the particular node's primary DAG parent, then the primary DAG parent is informed that it need not send distributed messages for the particular node. In another embodiment, a distributing node continues to repeat distributed messages in response to receiving notification that it is being used as a distributing parent, and if a primary DAG parent, prevents the repeating in response to receiving a notification from all of its child nodes that it need not send distributed messages.

Abstract: In one embodiment, in response to a trigger condition being detected at a particular location in a primary directed acyclic graph (DAG) in a computer network, a particular node in the primary DAG at the particular location may be determined to act as a remote stitched (RS)-DAG root for an RS-DAG at the particular location. The determined RS-DAG root may then be instructed to initiate the RS-DAG, the instructing indicating one or more properties for the RS-DAG that are based on the trigger condition and that are different from properties of the primary DAG. In another embodiment, a particular node receives instructions to initiate an RS-DAG as its RS-DAG root, initiates the RS-DAG, and relays messages of the RS-DAG with a primary root of the primary DAG.

Abstract: In one embodiment, a particular node in a computer network receives an indication of a number of child nodes of one or more potential parent nodes to the particular node in a primary directed acyclic graph (DAG). From this, the particular node selects a particular potential parent node with the highest number of child nodes as a secondary DAG parent for the particular node, and joins the secondary DAG at the selected secondary DAG parent (e.g., for multicast and/or broadcast message distribution). This may recursively continue, such that nodes gravitate toward parents with more children, potentially allowing parents with fewer children to relinquish their parental responsibilities.

Abstract: In one embodiment, a wireless transmitting node in a frequency hopping wireless network may determine whether a packet can be transmitted within a particular timeslot of a frequency hopping sequence based on a length of the packet. If unable to transmit the packet within the particular timeslot, the transmitting node extends the particular timeslot into a subsequent timeslot to allow transmission of the packet within the extended timeslot at a frequency associated with the particular timeslot. Once the extended timeslot ends, the transmitting node and receiving node hop frequencies into the subsequent timeslot to synchronize with the rest of the network that already hopped at the conventional rate. In another embodiment, a wireless receiving node may also extend the particular timeslot into a subsequent timeslot to allow reception of a packet that would extend beyond the particular timeslot, and may hop frequencies upon expiration of the extended timeslot.

Abstract: In one embodiment, a particular node in a wireless network may receive a wireless signal, and may determine whether the wireless signal is intended for itself In response to determining that the wireless signal is intended for the particular node, the particular node may transmit a non-colliding wireless carrier sense detected alert (CSDA) signal during the received wireless signal to request that other nodes within communication distance of the particular node refrain from transmitting for a duration of the received wireless signal. In another embodiment, a node listens on a first frequency for a wireless CSDA signal regarding a second (colliding) frequency, and in response to receiving a CSDA signal, may refrain from transmitting a wireless signal on the second frequency for the particular duration, or else (if not receiving a CSDA signal), may allow transmission of a wireless signal on the second frequency, accordingly.

Abstract: In one embodiment, a management device determines a topology of nodes in a network. Based on the topology, frequency hopping sequences are assigned (and notified) to the nodes such that each particular node of a certain set of the nodes is assigned a frequency hopping sequence on which to transmit that is different than frequency hopping sequences of neighbors and hidden neighbors of that particular node. In another embodiment, a transmitting node first transmits a transmission indication signal on its particular frequency band based on its frequency hopping sequence, and then transmits a message on the particular frequency band. In a further embodiment, a receiving node listening to a plurality of frequency bands may detect the transmission indication signal on the particular frequency band. In response, the receiving node filters out all frequency bands other than the particular frequency band, and receives the following transmission on that particular frequency band.

Abstract: In one embodiment, a receiving node in a computer network may detect congestion, and also identifies a set (e.g., subset) of its neighbor nodes. In response to the congestion, the receiving node may assign a transmission timeslot to each neighbor node of the set based on the congestion, where each neighbor is allowed to transmit (synchronously) only during its respective timeslot. The assigned timeslots may then be transmitted to the set of neighbor nodes. In another embodiment, a transmitting node (e.g., a neighbor node of the receiving node) may receive a scheduling packet from the receiving node. Accordingly, the transmitting node may determine its assigned transmission timeslot during which the transmitting node is allowed to transmit. As such, the transmitting node may then transmit packets only during the assigned timeslot (e.g., for a given time). In this manner, congestion at the receiving node may be reduced.

Abstract: In one embodiment, a particular node (e.g., root node) in a directed acyclic graph (DAG) in a computer network may identify a low-contact (e.g., wireless) node in the DAG that is at risk of having an invalid path when attempts are made to reach the low-contact node. In response, the particular node may identify neighbors of the low-contact node, and may establish a multicast tree from the particular node to the low-contact node through a plurality of the neighbors to reach the low-contact node. When sending traffic to the low-contact node, the particular node sends the traffic on the multicast tree, wherein each of the plurality of neighbors attempts to forward the traffic to the low-contact node. In another embodiment, the low-contact node itself indicates its status to the particular/root node, along with its list of neighbors in order to receive the multicast traffic.

Abstract: In one embodiment, one or more routing update parameters may be set for and propagated to nodes of a directed acyclic graph (DAG) in a computer network, the routing update parameters indicative of when to perform a corresponding routing update operation. A decision node (e.g., a root node of the DAG, application in a head-end, etc.) may gather network statistics of the DAG during operation based on the routing update parameters, and may accordingly determine at least one adjusted routing update parameter based on the gathered network statistics. This adjusted routing update parameter may then be propagated to the nodes of the DAG, such that the nodes operate according to the (adaptively) adjusted routing update parameter.

Abstract: In one embodiment, a node may determine a topology of a plurality of reporting nodes within a directed acyclic graph (DAG) in a computer network. The reporting nodes may then be assigned to one of a plurality of reporting groups, where reporting nodes are allowed to report only during designated time windows corresponding to their assigned reporting group. The reporting nodes may then be informed of at least their own assignment to a particular reporting group. In another embodiment, a particular reporting node may join the DAG, and may also receive an assignment to one of a plurality of reporting groups. Accordingly, the particular reporting node may also determine designated time windows corresponding to the assigned reporting group, where the particular reporting node is allowed to report only during the designated time windows.

Abstract: In one embodiment, a particular node joins a directed acyclic graph (DAG) in a computer network at a parent node, and determines its grade based on a topology of the DAG, the grade lower than the parent node and higher than any child nodes of the particular node. In response to detecting a trigger for a routing change in the DAG, the particular node delays the routing change based on the grade such that the delay is longer than a first associated delay of any of the child nodes and shorter than a second associated delay of the parent node. Upon expiration of the delay, the particular node may determine if the trigger for the routing change is still valid, and if valid, performs the routing change.

Abstract: According to one or more implementations of the disclosure, packets may be transmitted in a low power and lossy network (LLN) by receiving, on a first node, a message from a sending node, and by activating a critical message configuration to be applied in routing the message. A message identifier (e.g., signature) for the message may also be received or gleaned. The message identifier can be compared at the first node to a list of stored message identifiers, created based on routing history, to determine if the message has already been received. As such, if the message has not been received at the first node previously, a first parent and a second parent for the message are identified and the message, along with the critical message indication, can be transmitted to the first parent and the second parent, thereby achieving redundancy in the routing of the message.

Abstract: In one embodiment, a node may request to join a parent node in a directed acyclic graph (DAG) in a computer network, and may notify the parent node of a load associated with the request, and whether the node has any other parent node options. The response received from the parent node may be either an acceptance or a denial (based on the load and other parent node options), where in the case of an acceptance, the node may join the parent node in the DAG. Alternatively, in response to a denial, in one embodiment, the node may perform load shedding to become acceptable to the parent node. In another embodiment, a node receiving a join request from a child node may determine an impact associated with allowing the child node (and its load) to join the receiving node in the DAG prior to returning an acceptance or denial, accordingly.

Abstract: In one embodiment, a node may request to join a parent node in a directed acyclic graph (DAG) in a computer network, and may also notify the parent node of a load associated with the request and whether the node has any other parent node options. The requesting node may then receive a response from the parent node that is either an acceptance or a denial. While the node may join the parent node in response to an acceptance, if a denial is received, the node may divide the load into first and second portions, and may re-request to join the parent node with the load of the first portion. In this manner, by partitioning the load, a load balancing mode of operation across multiple is parents in a DAG is provided.

Abstract: In one implementation, a method of distributing a multicast message in a wireless mesh network includes receiving a multicast message from a parent node of an intermediate node. The method includes transmitting the multicast message to child nodes of the intermediate node. The method includes storing the multicast message in a cache at the intermediate node. The method includes intercepting an acknowledgement message from each acknowledging child node within an acknowledging subset of less than all of the child nodes. The method includes accessing information indicating a population of the child nodes to which the multicast message transmission was directed. The method includes comparing the acknowledging subset of the child nodes with the population of the child nodes. The method includes identifying a non-acknowledging subset of less than all of the child nodes. The method includes retransmitting the multicast message to the non-acknowledging subset of the child nodes.