Access Priority Schemes for UMTS MAC

UMTS is a third generation radio access network which supports multimedia-capable mobile communication such as packet data and Internet access. In order to provide end-to-end Quality of Service (QoS) in UMTS network, certain features need to be incorporated into the MAC design. One possible way of providing different QoS is via providing priority mechanisms. The priority mechanism can be implemented in terms of access priority, service priority and/or buffer management schemes. In this paper, we propose three access priority schemes based on the UMTS random access channel structure. The three schemes are: Random Chip Delay Access Priority (RCDAP), Random Backoff Based Access Priority (RBBAP), and Variable Logical Channel Based Access Priority (VLCAP). We discuss scenarios where such access priority schemes may be useful.