Quality-of-service attributes for packet-switched services in third-generation mobile systems (UMTS)

The third generation of mobile systems (UMTS) will provide different end-users data applications based on packet-switched services. In order to meet end-users' expectations and to overcome the limitation of system resources and the air interface capacity, it is necessary to properly define quality-of-service (QoS) attributes. This article gives an overview on UMTS services, lists QoS attributes used for packet-switched services and explains how they are defined to provide and maintain quality-of-service requirements for various types of connections in a packet-switched mobile environment. Considerations are based mainly on the technical characteristics and realisations of the W-CDMA standards, proposed by the 3GPP organisation and as such accepted for implementation in UMTS mobile systems.