Campbell Scientific PakBus Networking Guide - Manual (Page 6)

PakBus Networking Guide
Beacon: A broadcast message sent over the network by a node. All PakBus
devices must respond to a beacon by initiating a hello exchange unless an
allowed neighbor list prohibits communication with that node.
Beacon Interval: The interval specifying the rate at which beacons will be
issued to the network by a PakBus node.
Destination Address: The PakBus address of the node where a packet is
being sent.
Hello Exchange: The process of verifying a node as a neighbor. A hello
command is sent to a neighbor node and the exchange is complete once a hello
response comes back from the neighbor. To successfully send and receive
packets, network devices must maintain an accurate list of currently viable
links and devices using hello exchanges. If a device has not heard from a
certain neighbor within a period of time greater than the calculated verification
interval for those nodes, a hello exchange will be initiated to determine if the
node is still a viable neighbor.
Hop: The link between two adjacent nodes.
Hop Metric: An estimate of the time required to complete a transaction
between two adjacent nodes.
Leaf Node: A leaf node is a PakBus device that exists at the end of a network
segment or branch. The leaf node can’t route packets to other devices. It can
only send and receive packets meant for that device.
Neighbor: A PakBus node that is directly connected to or, in other words,
only takes one hop to communicate with another node. Before a PakBus node
considers another node to be a neighbor, the nodes must successfully
accomplish a hello exchange and periodically communicate in some manner.
After a successful hello exchange, the nodes establish each other as neighbors.
Network: A group of two or more PakBus devices that can communicate with
each other.
Node: In PakBus networking, a node is equivalent to a PakBus device and is
used to reference an element in the PakBus network. A node can be a
computer, datalogger, or communication peripheral that has its own PakBus
address.
PakBus Address: The identification number or address of the node. The
PakBus address is used to declare a source and destination node in
communication packets. Every PakBus device in a network needs a unique
PakBus address to receive, send, or route PakBus protocol packets.
PakBus Device: Any node that communicates using PakBus protocol.
Router: A PakBus device that forwards requests between devices that cannot
communicate directly with each other. Routers maintain a routing table, which
is a list of known nodes and routes. A router will only accept and forward
packets that are destined for known devices. Routers pass their lists of known
neighbors to other routers in order to build the network routing system.
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