based on the number of TS N (total system capacity), TS Nu and resource utilisation Resource utilization. This is the ratio between the PS traffic intensity and the total system capacity Ns. RTSL mean throughput. This is the product of the RTSL capacity and its utilization. Abis data rate reduction factor. The reduction of the mean throughput due to a lack of the transmission resources (i.e. it is the effect of sharing a few transmission resources to transport data coming from a higher number of RTSL or system capacity, Ns). The probability of successful trials for each call can be theoretically calculated using the following binomial distribution: (3.74) where N = number of timeslots available in the pool p = channel utilisation of the EDGE channels in the air interface Interface Planning n = number of traffic channels used in the air interface B = blocking probability of the DAP The formula basically tries to calculate how much the blocking on the Abis interface would be due to the (lack of) timeslots available in the pool. Obviously, a higher number of timeslots, i.e. a larger pool size, would mean less blocking, i.e. a lower probability of pool overflow. Inputs from the RNP are: RTSL utilisation RTSL capacity EGPRS territory (dedicated + default timeslots) While inputs from the TNP are: Abis data rate reduction factors (usually agreed with the RF and should be low, e.g. 0.1 %) Available TSs that can be used for the pool. Sharing of DAP Consider the following example where a DAP of three TSs is created. Each of these timeslots carry data traffic of coding schemes MCS-3, MCS-9, MCS-7, MCS-5 and MCS-6. The required number of slave Abis channels required is 11 (summation of the Abis slave channels required by the individual coding schemes). The DAP is designed with four timeslots, which mean 4 X 4 = 16 Abis channels. As the requirement is for 11 Abis (slave) channels, all the requests would be accommodated without any problems. MCS-3 MCS-5 MCS-6 MCS-6 MCS-7 MCS-7 MCS-7 MCS-9 MCS-9 MCS-9 MCS-9 Now consider the fol