Quality of Service Drivers in LTE and LTE-A Networks

In the last years, cellular operators have experienced a rapid growth of mobile broadband subscribers and traffic volume per subscriber. At the same time, operators are moving from a single to a multi-service offering by adding new services such as multimedia telephony and mobile-TV. In this challenging scenario, the Quality of Service (QoS) concept provides network and service operators with a set of tools to enable service and subscriber differentiation. This paper presents an overview of the QoS drivers in Long-Term Evolution (LTE) and LTE-Advanced (LTE-A) networks, focusing on their QoS policy control capabilities. Proposals of policy control and management for increasing the QoS in LTE and LTE-A networks are described. This paper also includes a detailed list and analysis of the inputs to the Policy and Charging Rules Function (PCRF) that can be used for policy decision as well as a set of use cases involving the Policy and Charging Control architecture: (1) the analysis of a potential cooperation between the PCRF and a Deep Packet Inspector, and (2) the analysis of a potential interaction between the PCRF and the radio scheduler to provide a consistent end-to-end QoS.