Performance of the AAL2 protocol within the UTRAN

The UMTS (Universal Mobile Telecommunication System) is the future network for mobile communication systems. The access network of UMTS is called UTRAN (Universal Terrestrial Radio Access Network). In Release 99 of the 3GPP standard, the AAL2/ATM protocol is chosen as a transport protocol within the UTRAN. In this paper, we studied some performance issues of the AAL2 protocol in the context of the UTRAN: the impact of the Timer-CU on traffic performance, the scheduling mechanism in the AAL2 multiplexer and the AAL2 switching. We show that an optimal value of the Timer-CU may be chosen in the case of a mono-service VC. We present a comparison between different scheduling mechanisms (WRR, EDF, FIFO, Priority) in order to chose the suitable algorithm for the CPS multiplexer and finally we present a comparison between the AAL2 switching and the ATM switching.