End-to-End Quality of Service in Evolved Packet Systems

The recent emergence of new IP-based services that require high bandwidth and low service latency such as voice over IP (VoIP), video sharing, and music streaming have motivated the 3rd Generation Partnership Project (3GPP) to work on the all IP-based cellular networks called Evolved Packet System (EPS). It is challenging for EPS not only to meet the Quality of Service (QoS) requirements of new services but also to make sure the QoS of existing services not impacted. In this chapter, the authors will first present an overview of EPS, and then focus on the aspects of QoS principles and mechanisms in EPS. End-to-end QoS models have been developed to analyze the application performance in EPS. Simulation results have shown that VoIP service requires resource reservation to guarantee its QoS requirement, and e-mail service does not experience significant performance degradation even when assigned a low service priority and the system experiences short period congestion. However, web browsing performance may not be improved proportionally to the network bandwidth increase due to the inherent network probing procedure of the transport protocol.