18-04-2012, 12:30 PM
SPIN
spin.ppt (Size: 481 KB / Downloads: 154)
Motivation
Dissemination is the process of distributing individual sensor observations to the whole network, treating all sensors as sink nodes
Replicating complete view of the environment
Enhance fault tolerance
Broadcast critical piece of information
Limited supply of energy
Energy-Conserving communication and computation
Limited computational power
Sophisticated network protocols not suitable
Limited communication resources
Communication bandwidth is limited to a few hundred Kbps
Implosion
Always sends data to a neighbor, even it has already received the data from another node
Function of topology
Overlap
Nodes often cover overlapping areas (e.g. temperature distr.)
Function of topology and mapping of observed data
Resource blindness
Amount of energy available does not affect the communication activities
simulation
no physical implementation but simulation with network simulator ns-2
event-driven network simulator
extensive support for simulation of: TCP, routing, multicast protocols
functionality of ns was extended to implement SPIN family, node class extended to create a Resource-Adaptive Node, components:
Summary
SPIN is family of data dissemination protocols
meta-data negotiation and resource adaptation
only transmit data when necessary, never waste energy on useless transmissions
when energy is low: node cuts back its activities
solved implosion and overlap problem
only local neighborhood information, thus well suited for mobile sensors
time performance: comparable to classic flooding
energy performance: 25% energy of classic flooding, SPIN-2 distributes 60% more data per unit energy than flooding
gossiping outperformed in both disciplines
close to ideal dissemination