Definition of "keepalive" []

• A short message sent by one device to another to check that the link between the two is operating. (noun)

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• "OSPF keepalive packet from a neighbor before assuming the device is down."
• "The interval that the router sends out keepalive packets across the virtual link to alert the other end of the link that the router is up."
• "The interval that the device sends out OSPF keepalive packets to let other routers know the device is up."