keepalive


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keepalive

In a communications session, a keepalive is a signal sent from one device to another in order to maintain the session or to determine if the line is down.
References in periodicals archive ?
The NAT-T, NAT keepalive and UDP encapsulation (UDP ports 500/4500) functions enable IPsec-connections to be established over any router, firewall or WLAN-Hotspot.
Similarly, the Base Node shall not reuse a LNID freed by the keepalive process until Tkeep_alive seconds have passed, using the last known acknowledged Tkeep alive value, or if larger, the last unacknowledged Tkeep_alive, for the Service Node using the LNID.
Failure detection time depends on the frequency with which downstream node sends keepalive requests to its upstream neighbors.
Inspite of periodically flooding a KEEPALIVE message to keep multiple paths alive and update cost functional metrics, we appends the metrics on the data message by attaching the remaining buffer size, link quality and residual energy, to the data message.
Also, keepalive messages are sent by clients during the long data transmission periods to inform that the multicasting session connection is still continuing.
The main drawback of this protocol is that the source should periodically flood KEEPALIVE messages over the multiple paths in path maintenance stage, which will impose high overhead.
This system will waste less power than phase control dimmers because the dimmer will not be controlling the power flowing to the load, and the lamps will not have to draw power not used to generate light just to provide the TRIAC keepalive current.
Nodes keep updated their neighbor table by sending keepalive messages to all their neighbors and waiting for a reply in less than 10 seconds.
A node assumes that its neighbor is down when it receives a leaving notification or when it has not received any response message during 10 seconds (e.g., after a keepalive message has been sent or in the path verification subprocess that takes place in the forwarding process).
Nodes will send keepalive messages periodically to their neighbors.