Nodes and methods for enabling user plane traffic classification in a communications system

A method performed by a Session Management Function (SMF) node for enabling user plane traffic classification in a communications system supporting Control Plane User Plane Separation (CUPS) with multiple User Plane Function (UPF) nodes, the method comprising:

• transmitting, to a Policy Control Function (PCF) node, a policy request for a User Equipment, UE;
• receiving, from the PCF node, a policy response comprising an indicator indicating Classification Optimization for Multiple User plane functions (COMU) for the UE;
• transmitting, to a first UPF node, a first detection rule to classify application traffic, first instructions rules to be applied to the classified application traffic and, based at least on the indicator indicating COMU, a class identifier to identify the classified application traffic towards a next UPF node;
• and
• transmitting, to a next UPF node, next detection rules to classify application traffic, next instructions rules for each next detection rule and to be applied to the classified application traffic and, based at least on the indicator indicating COMU, a class indicator indicating to classify an application traffic received from the first UPF node in accordance with the class identifier.

A method performed by a first User Plane Function (UPF) node for enabling user plane traffic classification in a communications system supporting Control Plane User Plane Separation (CUPS) with multiple UPF nodes, the method comprising:

• receiving, from a Session Management Function (SMF) node a first detection rule to classify application traffic, first instructions rules to be applied to the classified application traffic and a class identifier to identify the classified application traffic towards a next UPF node;
• detecting the application traffic with the first detection rule;
• classifying the application traffic in accordance with the first detection rule;
• applying the first instruction rules to the classified application traffic, and
• forwarding the application traffic toward the next UPF node along with the class identifier identifying a classification result.

A method performed by a next User Plane Function (UPF) node for enabling user plane traffic classification in a communications system supporting Control Plane User Plane Separation (CUPS) with multiple UPF nodes, the method comprising:

• receiving, from a Session Management Function (SMF) node, next detection rules to classify application traffic, next instructions rules for each next detection rule and to be applied to the classified application traffic, and a class indicator indicating to classify an application traffic received from a first UPF node in accordance with a class identifier identifying a classification result;
• receiving the application traffic from the first UPF node along with the class identifier identifying the classification result;
• based on the class indicator, determining a second detection rule amongst the next detection rules, wherein the second detection rule matches the classification result identified in the class identifier;
• and
• classifying the received application traffic in accordance with the second detection rule and applying instruction rules for the second detection rule to the received application traffic.

A Session Management Function (SMF) node for enabling user plane traffic classification in a communications system supporting Control Plane User Plane Separation (CUPS) with multiple User Plane Function (UPF) nodes, the SMF comprising:

• communication interface circuitry configured to communicate with the multiple UPF nodes and a Policy Control Function (PCF) node;
• and
• processing circuitry and memory operatively coupled to the communication interface circuitry and configured to control the communication interface circuitry to:
• transmit, to a Policy Control Function (PCF) node, a policy request for a User Equipment, UE;
• receive, from the PCF node, a policy response comprising an indicator indicating Classification Optimization for Multiple User plane functions (COMU) for the UE;
• transmit, to a first UPF node, a first detection rule to classify application traffic, first instructions rules to be applied to the classified application traffic and, based at least on the indicator indicating COMU, a class identifier to identify the classified application traffic towards a next UPF node;
• and
• transmit, to a next UPF node, next detection rules to classify application traffic, next instructions rules for each next detection rule and to be applied to the classified application traffic and, based at least on the indicator indicating COMU, a class indicator indicating to classify an application traffic received from the first UPF node in accordance with the class identifier.