Method and apparatus for assigning network address prefix

A method performed by a user plane function, comprising:

• receiving, from a control plane function, a Packet Forwarding Control Protocol, PFCP, Session Modification Request for requesting the user plane function to assign a network address prefix to a terminal device;
• transmitting, to the control plane function, a PFCP Session Modification Response including an assigned network address prefix,
• wherein the PFCP Session Modification Request includes a first parameter indicating that the user plane function is delegated to assign the network address prefix, and wherein the PFCP Session Modification Response includes a second parameter indicating assigned network address prefix by the user plane function;
• wherein the PFCP Session Modification Request includes a field for IPv6 Prefix Delegation Bits and/or a field for IPv6 Prefix Length;
• wherein the field for IPv6 Prefix Delegation Bits and/or the field for IPv6 Prefix Length indicates a length of the network address prefix, or the field for IPv6 Prefix Delegation Bits and/or the field for IPv6 Prefix Length is set to zero to indicate that the user plane function determines the length of the network address prefix based on a local configuration.

A control plane function, comprising:

• one or more processors;
• and
• one or more memories comprising computer program codes,
• the one or more memories and the computer program codes configured to, with the one or more processors, cause the terminal device at least to:
• receive, from a terminal device, a request for assigning a network address prefix;
• determine whether the network address prefix is to be assigned by the control plane function or a user plane function;
• transmit, to the user plane function, a Packet Forwarding Control Protocol, PFCP, Session Modification Request for requesting the user plane function to assign the network address prefix, if it is determined that the network address prefix is to be assigned by the user plane function;
• receive, from the user plane function, a PFCP Session Modification Response including an assigned network address prefix;
• and
• transmit the assigned network address prefix to the terminal device,
• wherein the PFCP Session Modification Request includes a first parameter indicating that the user plane function is delegated to assign the network address prefix, and wherein the PFCP Session Modification Response includes a second parameter indicating assigned network address prefix by the user plane function;
• wherein the PFCP Session Modification Request includes a field for IPv6 Prefix Delegation Bits and/or a field for IPv6 Prefix Length;
• wherein the field for IPv6 Prefix Delegation Bits and/or the field for IPv6 Prefix Length indicates a length of the network address prefix, or the field for IPv6 Prefix Delegation Bits and/or the field for IPv6 Prefix Length is set to zero to indicate that the user plane function determines the length of the network address prefix based on a local configuration.

A user plane function, comprising:

• one or more processors;
• and
• one or more memories comprising computer program codes,
• the one or more memories and the computer program codes configured to, with the one or more processors, cause the terminal device at least to:
• receive, from a control plane function, a Packet Forwarding Control Protocol, PFCP, Session Modification Request for requesting the user plane function to assign a network address prefix to a terminal device;
• transmit, to the control plane function, a PFCP Session Modification Response including an assigned network address prefix,
• wherein the PFCP Session Modification Request includes a first parameter indicating that the user plane function is delegated to assign the network address prefix, and wherein the PFCP Session Modification Response includes a second parameter indicating assigned network address prefix by the user plane function;
• wherein the PFCP Session Modification Request includes a field for IPv6 Prefix Delegation Bits and/or a field for IPv6 Prefix Length;
• wherein the field for IPv6 Prefix Delegation Bits and/or the field for IPv6 Prefix Length indicates a length of the network address prefix, or the field for IPv6 Prefix Delegation Bits and/or the field for IPv6 Prefix Length is set to zero to indicate that the user plane function determines the length of the network address prefix based on a local configuration.