3.2.2 Timers

Retransmission Timer: This timer SHOULD be used by the protocol client for retransmission of the Allocate request and Set Active Destination request messages when the protocol client fails to receive a response from the TURN server. The protocol client SHOULD start this timer when the request message has been sent to the wire. The protocol client SHOULD retransmit these request messages at a fixed interval of 650 milliseconds. The protocol client SHOULD retransmit a maximum of nine times before assuming the transaction and TURN session are no longer valid.