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    | l | 
    “Pull” vs.
    “push” delivery of information 
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    – | 
    Do your messages
    find you, or do you have to look 
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    for them? 
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    – | 
    The “message
    waiting” light and notification 
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    l | 
    Mobile vs. office 
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    | l | 
    Always-on,
    always connected is key enabler. 
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    – | 
    No action
    required to receive messages 
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    – | 
    Messages can be
    queued when out of range, then 
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    automatically
    delivered 
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