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    | l | 
    Basic
    Idea: 
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    u | 
    Predict
    the link breakage time (prediction algorithm) 
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    Rebuild
    a route before link breaks (pro-active route maintenance) 
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    Invalidate
    cached routes before they become stale 
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    | l | 
    Prediction
    Algorithm 
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    u | 
    Monitor
    unicast packets from neighboring nodes 
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    u | 
    Using
    signal power strength to predict the link breakage time 
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