El problema es más crítico en el caso de la red de acceso, donde habitualmente los recursos radio y de transmisión suelen ser escasos. Resumen El soporte eficiente de múltiples clases de tráfico con diferentes requisitos de calidad de servicio plantea nuevos problemas de ingeniería a la hora de diseñar una red de comunicaciones móviles de tercera generación (3G).
Some preliminary results obtained with the simulator are presented in order to illustrate This wide range of applications has led us to develop a very flexible simulation model thatĬaptures many low level details. To use the tool for dimensioning ATM links, for evaluating performance under different mixes of traffic classes, and for investigating Provide a test bed for conducting further research studies on several topics of potential interest. Of the ATM-based UMTS (Universal Mobile Telecommunications System) terrestrial radio access network. In this paper we present a simulation model This task becomes especially criticalįor the access network, where radio and transmission resources are usually scarce. Loss) poses an extraordinary complexity in the design of third-generation mobile networks. The efficient support of multiple traffic classes with different quality of service requirements (end-to-end delay, jitter, The use of RLP(1,2,3) puts the session setup time down to 2.4 s under UDP and 3.5 s under TCP for the same FER and the same channel bandwidth. For a 9.6 Kbps channel, the SIP session setup time can be up to 84.5 s with UDP and 105 s with TCP when the FER is up to 10%. In this paper, we focus on the SIP protocol and evaluate its session setup delay with various underlying protocols (transport control protocol (TCP), user datagram protocol (UDP), radio link protocol (RLP)) as a function of the FER. One way to do so is by choosing the appropriate retransmission timer and the underlying protocols. Therefore, such protocols should have a session setup time optimized against loss. The session setup time can be affected by the quality of the wireless link, measured in terms of frame error rate (FER), which can result in retransmission of lost packets and can lengthen the session setup time. Signalling protocols such as the session initiation protocol (SIP) are used to set up VoIP calls.
Wireless networks beyond 2G aim at supporting real-time applications such as VoIP.
0 kommentar(er)
