Digi International Inc XBEEPRO2 Manual Do Utilizador

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© 2011 Digi International, Inc.
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Appendix A: Definitions
Definitions
ZigBee Node Types
Coordinator
A node that has the unique function of forming a network. The coor-
dinator is responsible for establishing the operating channel and PAN 
ID for an entire network. Once established, the coordinator can form 
a network by allowing routers and end devices to join to it. Once the 
network is formed, the coordinator functions like a router (it can par-
ticipate in routing packets and be a source or destination for data 
packets).
  -- One coordinator per PAN
  -- Establishes/Organizes PAN
  -- Can route data packets to/from other nodes
  -- Can be a data packet source and destination
  -- Mains-powered
Refer to the XBee coordinator section for more information.
Router
A node that creates/maintains network information and uses this 
information to determine the best route for a data packet. A router 
must join a network before it can allow other routers and end 
devices to join to it.
A router can participate in routing packets and is intended to be a 
mains-powered node.
  -- Several routers can operate in one PAN
  -- Can route data packets to/from other nodes
  -- Can be a data packet source and destination
  -- Mains-powered
Refer to the XBee router section for more information.
End device
End devices must always interact with their parent to receive or 
transmit data. (See ‘joining definition.) They are intended to sleep 
periodically and therefore have no routing capacity. 
An end device can be a source or destination for data packets but 
cannot route packets. End devices can be battery-powered and offer 
low-power operation.
 -- Several end devices can operate in one PAN
 -- Can be a data packet source and destination 
 -- All messages are relayed through a coordinator or router
 -- Lower power modes