Establishing a communication session

A method of operating a Policy and Charging Rules Function to facilitate a communication session over an IP Connectivity Access Network between a user terminal and an Application Function, the method comprising:

• receiving information relating to the session from the Application Function;
• determining one or more Policy and Charging Control rules for the session, including deriving a Quality of Service authorised for the session;
• sending the Policy and Charging Control rules, including the authorised Quality of Service, to a Policy and Charging Enforcement Function;
• receiving a report from the Policy and Charging Enforcement Function that the authorised Quality of Service cannot be achieved due to a limitation on a Quality of Service available in the Access Network, the report including the available Quality of Service;
• and
• using the available Quality of Service to determine whether and/or how to maintain the session.

An apparatus configured to operate as a Policy and Charging Enforcement Function to facilitate a communication session over an IP Connectivity Access Network between a user terminal and an Application Function, the apparatus comprising:

• a receiver for receiving one or more Policy and Charging Control rules for the session from a Policy and Charging Rules Function, including a Quality of Service authorised for the session;
• a processing unit for determining if there is a limitation on a Quality of Service available in the Access Network that prevents the authorised Quality of Service from being achieved and, if so, for generating a report reporting this to the Policy and Charging Rules Function including the available Quality of Service;
• and
• a transmitter for sending the report to the Policy and Charging Rules Function.

An apparatus configured to operate as a Policy and Charging Rules Function to facilitate a communication session over an IP Connectivity Access Network between a user terminal and an Application Function, the apparatus comprising:

• a receiver for receiving information relating to the session from the Application Function;
• a rules generation unit for determining one or more Policy and Charging Control rules for the session, including deriving a Quality of Service authorised for the session;
• a transmitter for sending the Policy and Charging Control rules, including the authorised Quality of Service, to a Policy and Charging Enforcement Function;
• a receiver for receiving a report from the Policy and Charging Enforcement Function that the authorised Quality of Service cannot be achieved due to a limitation on the Quality of Service available in the Access Network, the report including the available Quality of Service;
• and
• a processing unit for using the available Quality of Service to determine whether and/or how to maintain the session.