Th`ese de Doctorat de l'université Paris VI Pierre et Marie Curie Mlle ...

static allocation is evident both in terms of accepted load and network revenue. More
specifically, OBA achieves the best performance in terms of network revenue especially for
high offered loads; note that IDBA achieves almost the same performance as SDBA for
medium offered loads.
7.2.2 Simple Core Network Scenario
A more realistic scenario is shown in Figure 7.14. It comprises 6 nodes and 8 bidirectional
links, all having a capacity equal to 2 Mb/s and propagation delay of 1 ms. In this topology,
6 Exponential On-Off traffic sources are considered, and their source and destination nodes
are indicated in the Figure. Table 7.1 reports the peak rate, the subscribed rate, the utility
function and the path for all the connections. Sources S1, S2 and S3 are associated the
utility function 0.5·log(1+x) while the remaining sources are associated the utility function
1.5 · log(1 + x). All other parameters are set as in the previous scenarios. Note that,
with such paths choice, various connections compete for network capacity with different
connections on different links.
In this scenario, the performance of IDBA almost overlaps that of OBA. This is expected
because the number of connections entering the network (i.e. 6) is quite small to gauge
the potential of OBA. Further, all the proposed algorithms (SDBA, IDBA and OBA)
outperform static allocation, as shown in Figures 7.15 and 7.16, thus proving the benefit
of the proposed schemes. These results verify that our allocation algorithms allow service
providers to increase network capacity utilization and consequently network extra-revenue
with respect to static provisioning techniques.
7.2.3 Multi-Bottleneck Scenario
We then consider the network topology shown in Figure 7.17, originally proposed in [1].
It comprises 8 core nodes and 7 bidirectional links, all having the same propagation delay,
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