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Chapter 4Simulation and analytical modelling pFigures 4.18 and 4.19 show the average end-to-end delays and throughput forsimulation and analytical results, respectively, as the offered load in increased for thesix different packet sizes presented in Table 4.2. For each packet, the offered load (λ)was increased from a relatively low rate at 16 kbps, up to approximately 98% of themaximum theoretical throughput. Offered loads close to 100% of the maximumthroughput were not considered, since the stability of the M/G/1 systems [10] requiresλ < 1.Table 4.2 – Maximum theoretical throughput for different packet sizes.Packet Size (bytes)Throughput (Kbps)3000270024002100180015001200900600300Max. Service Time X (ms)Max. Throughput (S max )64 2.24 228 kbps (≈ 4 % of the cc)128 2.24 456 kbps (≈ 7 % of the cc)256 2.24 912 kbps (≈ 15 % of the cc)512 2.99 1368 kbps (≈ 22 % of the cc)1024 3.74 21876 kbps (≈ 35 % of the cc)1518 Throughput 4.49 for Simulation and Theoretical 2703 kbps (≈ Results 44 % of the cc)0Simulation ResultsTheoretical Results64-bytepacket256-bytepacket128-bytepacket1024-bytepacket512-bytepacket1518-bytepacket0 250 500 750 1000 1250 1500 1750 2000 2250 2500 2750 3000Offered Load (Kbps)Figure 4.18 – System throughput: simulation and theoretical resultsfor different packet sizes.4-32