Mpls Overlay Network Sinthesis Method With Multilayer Graph Usage
  l. Introduction Modern network are multi-layer by their structure. This requires the development of new mathematical models, which would allow to adequately describe the existing physical and logical connections between the elements on its different levels, and to effectively solve the problems of design. The paper formulates the problem of synthesis of structure of MPLS network layered with the transport SDH network or WDM and suggests the method of its solving. The solving is based on the application of mathematical model of multi-layer graph. II, III, IV. Main Part During the planning of MPLS networks it is necessary to determine the topology of both the networks: that of transport one and that of MPLS one. This means that one needs to determine: - what nodes of the transport network should support the MPLS functionality; - in what way the LSR nodes should be connected via the transport network; - what should be the bandwidth between LSR links. According to the general method for solving the problem of synthesis of multiservice telecommunication systems with the usage of multi-layer graphs, we have to synthesize the initial redundant . The solving of the task above can be reduced to the finding of the multi-layer minimum weight subgraph that provides the transfer of information flows with the consideration of the requirements to the structure of the multilayer graph [5] and the flows on its edges [6] observed at the applying of constraints to the bandwidth of the edges of the multi-layer graph. V. Conclusion The paper reduces the problem of design of multiservice telecommunication system with the transferred flows to the problem of finding a multilayer minimum weight subgraph with the consideration of constraints to the graph edges bandwidth. It is shown that application of given method provide to reduce MPLS network cost to 10 - 16 %. 
Dmytro Ageyev, Haidara Abdalla, O. Starkova
cs.NI