Methods of handling an overload situation of a session initiation protocol, SIP node in a telecommunication network, as well as related SIP nodes

A method of handling an overload situation of a Session Initiation Protocol, SIP, node in a telecommunication network, wherein the method comprises:

• receiving, by a service SIP node in the telecommunication network, from a proxy SIP node in the telecommunication network, an SIP request for requesting a service in the telecommunication network;
• detecting, by the service SIP node, an overload situation at the service SIP node;
• and
• transmitting, by the service SIP node, to the proxy SIP node, a Server Failure Response message, the Server Failure Response message comprising an indication that the service SIP node cannot fulfil the SIP request due to an overload situation at the service SIP node and a SIP Reason Header field including automatic congestion level information, the Server Failure Response message triggering the proxy SIP node to restrict future SIP traffic to the service SIP node including preventing at least one message from being transmitted, by the proxy SIP node, to the service SIP node.

A proxy Session Initiation Protocol, SIP, node for supporting the handling of an overload situation of a SIP node in a telecommunication network, the proxy SIP node comprising:

• receive equipment configured to receive an SIP request for requesting a service in telecommunication network;
• transmit equipment configured to forward the SIP request to a service SIP node in the telecommunication network;
• the receive equipment being further configured to receive, from the service SIP node, a Server Failure Response message, the Server Failure Response message comprising an indication that the service SIP node cannot fulfil the SIP request due to an overload situation at the service SIP node and a SIP Reason Header field including automatic congestion level information;
• and
• the proxy SIP node further comprises process equipment configured to restrict future SIP traffic to the service SIP node based on the received Server Failure Response message, restricting the future SIP traffic including preventing at least one message from being transmitted, by the proxy SIP node, to the service SIP node.