In order for the Gatekeeper to determine if an endpoint is turned off, or has otherwise entered a failure mode, the Gatekeeper may use the Information Request (IRQ) to poll the endpoints at the certain interval (in seconds). THE IRQ INTERVAL controls the frequency the gk sends IRQ messages. This message is sent to all on-line endpoints registered as dynamic in order to verify they are really on-line. This is done to detect terminals that shut off without sending the required URQ message that notifies the gk that they are no longer on-line. Endpoints failing to respond too many times have their dynamic properties unregistered. Choosing the desired interval should take into account the following factors : IRQ messages add to the traffic already present over the network and the shorter the interval the more IRQ messages will be sent. On the other hand the longer the delay the longer it will take for the gk to detect dynamic registrations that have ceased to actually be on-line. Note that the IRQ interval relates to each endpoint and the actual number of the IRQ messages the gk will create should be multiplied by the number of endpoints registered dynamically.