Method and system for determining a quality of experience during a real-time communication session

1. A method for determining, in a communication system, a Quality of Experience associated with a real-time communication session between user devices of the communication system, the method comprising:

starting the real-time communication session;

monitoring the real-time communication session and determining, during the real-time communication session, at least one quality indicator indicative of the Quality of Experience, and at least one first performance indicator indicative of a Quality of Service and at least one second performance indicator indicative of the Quality of Service;

based on a self-learning process to which the at least one quality indicator and the at least one first performance indicator are applied, determining and continuously updating a correlation function indicative of the correlation between the Quality of Experience and the Quality of Service in respect of the monitored real-time communication session;

determining a parameter of the Quality of Service depending on both the at least one first performance indicator and the at least one second performance indicator, and

applying said parameter to the correlation function to determine said Quality of Experience,

wherein said determining a correlation function includes determining a value of at least one coefficient of the correlation function based on a previous value of the coefficient of the correlation function, and

the at least one second performance indicator comprises jitter buffer size.

2. The method according to claim 1 , wherein said determining a correlation function between the Quality of Experience and the Quality of Service in respect of the monitored real-time communication session further comprises determining said correlation function in respect of the monitored real-time communication session among a family of correlation functions being indicative of the correlation between the Quality of Experience and a Quality of Service in respect of a generic real-time communication session.

3. The method according to claim 2 , wherein said determining a correlation function comprises:

providing said correlation function family, and

based on the at least one quality indicator and the at least one first performance indicator, determining a value of at least one other coefficient of the correlation function family and applying the determined value of the at least one other coefficient to the correlation function family to determine the correlation function in respect of the monitored real-time communication session.

4. The method according to claim 3 , wherein said determining a value of at least one other coefficient of the correlation function family is based on at least one previous value of said at least one other coefficient.

5. The method according to claim 4 , wherein said at least one previous value of said at least one other coefficient is associated each one with a respective previous real-time communication session started by a same user device.

6. The method according to claim 1 , wherein the at least one first performance indicator comprises one or more among jitter and packet loss.

7. The method according to claim 1 , wherein the at least one quality indicator comprises the Mean Opinion Score.

8. The method according to claim 7 , wherein said determining at least one quality indicator comprises determining the Mean Opinion Score according to E-model transmission rating model defined in ITU-T G107 Recommendation.

9. The method according to claim 7 , wherein the Mean Opinion Score is associated with one or more among the user devices of the real-time communication session.

10. The method according to claim 1 , wherein said correlation function family is indicative of an exponential correlation between the Quality of Experience and the Quality of Service.

11. The method according to claim 1 , wherein said correlation function family is based on IQX hypothesis.

12. The method according to claim 1 , wherein said monitoring at least one quality indicator, and at least one first performance indicator and at least one second performance indicator is carried out over at least one among:

a network interface between a radio base station of the communication system and a Serving Gateway module of the communication system;

a network interface between the Serving Gateway module of the communication system and a Packet Data Network Gateway module of the communication system;

a radio interface between a Proxy-Call Session Control Function module of the communication system and an Interrogating/Serving Call State Control Function module of the communication system.

13. The method according to claim 1 , further comprising repeating said:

determining at least one quality indicator of the Quality of Experience, and at least one first performance indicator of the Quality of Service and at least one second performance indicator of the Quality of Service;

determining a correlation function;

determining a parameter of the Quality of Service, and

applying said parameter,

while the real-time communication session is in progress.

14. A method for determining, in a communication system, a Quality of Experience associated with a real-time communication session between user devices of the communication system, the method comprising:

starting the real-time communication session;

monitoring the real-time communication session and determining, during the real-time communication session, at least one quality indicator indicative of the Quality of Experience, and at least one first performance indicator indicative of a Quality of Service and at least one second performance indicator indicative of the Quality of Service;

based on a self-learning process to which the at least one quality indicator and the at least one first performance indicator are applied, determining and continuously updating a correlation function indicative of the correlation between the Quality of Experience and the Quality of Service in respect of the monitored real-time communication session;

determining, a parameter of the Quality of Service depending on both the at least one first performance indicator and the at least one second performance indicator, and

applying said parameter to the correlation function to determine said Quality of Experience,

wherein said determining a correlation function includes determining a value of at least one coefficient of the correlation function based on a previous value of the coefficient of the correlation function, and

said parameter comprises an effective packet loss depending on jitter, packet loss and jitter buffer size.

15. A communication system comprising:

at least one measurement device configured to monitor and perform measurements on a real-time communication session between user devices of the communication system thereby allowing to determine, during the real-time communication session, at least one quality indicator indicative of a Quality of Experience, and at least one first performance indicator indicative of a Quality of Service and at least one second performance indicator indicative of the Quality of Service; and

a processing device configured to, based on a self-learning process to which the at least one quality indicator and the at least one first performance indicator are applied, determine and continuously update a correlation function indicative of the correlation between the Quality of Experience and the Quality of Service in respect of the monitored real-time communication session, determine a parameter of the Quality of Service depending on both the at least one first performance indicator and the at least one second performance indicator, and apply said parameter to the correlation function to determine said Quality of Experience,

wherein in determining the correlation function, the processor determines a value at least one coefficient of the correlation function based on a previous value of the coefficient of the correlation function, and

the at least one second performance indicator comprises jitter buffer size.