sor sharing still performs among all active TCP flows, regardless of which RAB type they are using. Because the actual transmission rate of each flow is in fact controlled by TCP as a result of TCP flow control mechanism, which is designed to adapt the data rate to the available network bandwidth. TCP Flow RAB type 1 lub link (bandwidth C) RAB type 2 NodeB File arrival rate per RAB type RAB type 3 Bandwidth of user connection of RAB type i: ri User Equipment (UE) Figure 6.21: Flow level model for multiple RAB scenarios The principle of processor sharing in this case is illustrated in Figure 6.22. Based on this theory, it can be assumed that all active flows are sharing the lub link capacity quasi equally, and thus the lub link can be still modeled as a PS system. But since there are multiple peak rates, the original M/G/R-PS model, which is used for the case of one peak data rate, cannot be directly applied. Therefore a general form of the M/G/R-PS model is proposed in the framework of this thesis for the dimensioning of a general multiple RABs scenario. RAB type 1 (r1) PS-System RAB type 2 (r2) RAB type 3 (r3) RAB type 4 (r4) Figure 6.22: Processor Sharing 6.3 Dimensioning for Elastic Traffic The main idea of this analytical approach is to calculate the application performance for each elastic traffic class individually with the M/G/R-PS model. However, the M/G/R-PS model needs to be extended to consider bearer specific characteristics of each traffic class as well as processor sharing among all traffic flows of different bearers. Based on these considerations, a general form of M/G/R-PS model is proposed in this thesis to apply for individual bearer type or traffic class. The general form is extended from the original M/G/R- PS model, but for each traffic class the derivation of R is dependent on the peak rate of its selected bearer type (RAB type). This is based on the fact that the expected application performance of each traffic class is related to its own peak rate. When the link starts to be congested (i.e