Method by which nwdaf transmits and receives signal in wireless communication system, and device therefor

A device for use in a wireless communication system comprising:

• at least one processor;
• and
• at least one computer memory operatively connected to the at least one processor, and configured to store instructions such that the at least one processor performs specific operations by executing the instructions,
• wherein the specific operations include:
• receiving, by the NWDAF, a notification message based on a change of a user plane congestion status from operations and maintenance (OAM);
• and transmitting, by the NWDAF, a user plane congestion analytics notification based on the notification message to a V2X application server through a network exposure function (NEF),
• wherein the change of the user plane congestion status is determined based on at least one information including specific information indicating whether a QoS Notification Control (QNC) notification has been transmitted;
• and
• wherein the specific information indicating whether the QNC notification has been transmitted is determined based on a counter value that increases when an NG-RAN transmits ‘GFBR cannot be fulfilled/guaranteed’ to a session management function (SMF) and decreases when the NG-RAN transmits ‘GFBR cannot be fulfilled/guaranteed’ to the SMF.