ConEx Based QoE Feedback to Enhance QoS

Quality of service (QoS) generally represents the performance of packet networks. Quality of experience (QoE) defines the quality perceived by end-users of applications running on these networks. This paper relates these two metrics in a novel way using the newly defined congestion exposure (ConEx) mechanism. ConEx is an experimental protocol defined by the IETF that allows the sender of a flow to convey the received explicit congestion notification (ECN) information back into the network. In IPv6, ConEx is implemented in an option header with 28 unused bits. These bits can be used to convey more than ECN feedback towards the network. This paper proposes to use these bits to send real-time objective QoE information, as perceived by the end-users, into the network. Routers can leverage this information to adjust QoS mechanisms. As an example, a new queue management technique is proposed with a multi-field DiffServ classifier using the QoE metric. Simulation results show that this mechanism can help in improving the overall QoE of active flows.