Devices, systems, and methods for sending and processing session initiation protocol (SIP) responses are disclosed. According to one aspect, a method for sending an SIP response through a first telecommunications network node is described. The method includes receiving, by means of the first node, a SIP request sent by means of a second node of the network. The method includes detecting an event that interferes with processing of said request by means of the first node. The method further includes sending, to the second node, a SIP response notifying said interference. The method also includes, before the sending step, activating, within the SIP response, a parameter that allows the request to be rerouted, said parameter being configurable by means of the second node.