In candidate set selection, each node would periodically broadcast a beacon packet
to one hop neighbour with their residual energy and depth local information.
The parent selection mechanism is done by utilizing DFS (distance from the sink) field in the beacon packet
, which defines the distance of current CH from the sink.
After receiving this beacon packet
, the upstream node controls the sending rate by stopping to send the packets into the area of congestion.
When the sensor nodes of one-hop neighbors of the boundary nodes in the QR region receive the query packet, a beacon packet
has to be transmitted by those nodes.
In an operational cycle, after waking up each nonsender node immediately broadcasts a beacon packet
. The beacon contains the node's address aiming to announce that the node is ready for receiving a data packet.
To reduce network overhead, we embed all of the atomic messages into the beacon packet
The superframe is bounded with beacon packet
which is transmitted by the coordinator to all sensor nodes at the first two slots of each SF.
In fact, as in large-scale wireless sensor networks, every 3 bytes of each single beacon packet
(i.e., 2 bytes for identity of a given node and 1 byte for the number of received beacons from the corresponding node) should be allocated to share the related information of a single node and the payload size of TinyOS packets is 29 bytes, each beacon message can include the identity and data transmission quality of up to 9 nodes.
This routing framework estimates hop-to-hop delay, link reliability, and node temperature and exchanges those metrics through beacon packet
among neighboring nodes to have an end-to-end estimate of delay, reliability, and temperature of the routes from the nodes to the BC.
Through 1-hop neighborhood the route path is selected and the nodes position are monitored by setting predefined threshold values and if it exceeds the value beacon packets
are sent to the neighboring nodes to update their neighbor list to maintain their local topology.
Each node broadcasts beacon packets
periodically which contain their own routing information such as the ETX and parent to do the routing job.
In beacon enabled mode of IEEE 802.15.4, beacon packets
are required for broadcast, which results in overhead.