cket over SONET using the full GFP in a mesh network Packet over SONET using the full GFP in a ring network No switching below the MPLS router, routers are connected to the other routers with bare open WDM systems MPLS over OTN: physical mesh with electrical core OXCs MPLS over OTN: physical multiring 1:1 OChDPring As far as the traffic is concerned, since the IP layer is not simulated, the higher layer that is dimensioned in the program is SDH/SONET or MPLS. In both the cases, the traffic is represented via requests of connectivity. In the static case, the requested traffic is organized in a traffic matrix, in the dynamic case, the requests of connectivity are generated through a mechanism in the IP layer that is not reproduced in the model. As far as layer 2 is concerned, the requests present them- selves as a Poison process. In both the cases, two QoS classes are considered: real-time services that have limitation in the maximum delay and need fast protection and best effort services that have no maxi- mum delay requirement and face network failures only via restoration. Telecommunication Networks Norden Hamburg Bremen Berlin Hannover Essen Düsseldor Dortmund Leipzig Frankfu Mannheir Nümberg Karlsrub Stuttgart FIGURE 3.55 München Topology of the German long haul network used in some examples of network cost evaluation. In all the cases that we are going to show here, the two classes of QoS have the same number of trails requested from the IP. 3.4.4 Cost Comparison Starting with static traffic, it is important to study first of all the behavior of the total CAPEX needed to deploy the network. In Figure 3.57, the total CAPEX is shown versus the traffic for the three solutions with a mesh physical architecture. Both the traffic intensity and the CAPEX are relative. Moreover, let us remember that the CAPEX is calculated as costs for the vendors; thus, it does not include the vendor margin. The solution interfacing directly the LSR and LER with the DWDM systems is the more expensive, as it was easy to imagine, sinc