Université Des Sciences Et De La Technologie DOran Mohamed Boudiaf USTO République Algérienne Démocratique et Populaire Département de linformatique Projet en Recherche Opérationnelle Routing Optimization Thème Membre du groupe : MAAMERI Meryem Nedjwa KHECHIBA Hanane Chef du groupe : KHECHIBA Hanane

SUMMARY Introduction Fundamentals 2.1 routers 2.2 routing optimization problems 3.1 optimization of routers 3.2 optimization of routing metrics ip Conclusion 2

I NTRODUCTION : One of the primary goals of all routing protocols is to select the most optimal path through the network from the source subnet to the destination subnet. The most optimal route depends on the metrics used by the routing protocols. 3

4 ROUTERS : A Router is a device that connects two networks - frequently over large distances. It understands one or more network protocols, such as IP. Figure 1 : representation of a router

5 R OUTING The routing code controls the flow of all packets within the networking subsystem. It makes the decision of where a packet with a given destination address should be sent next.

problem of optimal routing problem of optimal routing 6

D EFINITION the routing optimisation problem is a technique used to optimize the flow of the packages on a node.. 7 Figure 2: reception of the packages in a router.

O BJECTIVES OF THE OPTIMISATION Find the objective function. Minimization of the total flood by the cost function Reducing the congestion of the links. Increase the capacity of the network. 8

M ODELING THE PROBLEM There are two functions : Additive cost function. Non-additive cost function. 9

Additive cost function : i,j : nodes D ij : represente the congestion on the link(i,j). C ij : capacity of transition in a link (i,j) measured in package / second. Flow on the links. 10

N OTATION : r w : the rate of reception the package to the node o to the destination d. W : all couples origine-destination. P w : all way between the couple OD w. X p : the flow in package / second transmitted on the road p 11

F LOW ON THE LINKS : The total traffic on link (i,j) the sum of waves which pass through this link. 12

General formalization of the problem 13

E XAMPLE Demandes r 15 et r 23 : w= {(1,5), (2,5)}. Chemins de r 15 : p 15 = {p 1, p 2 } ou p 1 = {1, 3,5} et p 2 = {1, 2, 4,5}. Chemins de r 23 : p 23 = {p 3, p 4 } ou p 3 = {2, 1,3} et p 4 = {2, 4,3}. 14

E XAMPLE 15

To conclude, with these results we have achieved our objectives cited earlier. 16 C ONCLUSION

L ISTE DES F IGURES Figure 1: Représentation des routeurs Figure 2 : Représentation darrivé des paquets dans un routeur. Figure 3 : Exemple représentant le flot sur les chemins. Figure 4 : Modélisation du problème. Figure 5 : Exemple représentant un réseau avant loptimisation. Figure 6 : Exemple représentant un réseau à loptimisé. 17

L ES R ÉFÉRENCES Olivier BRUN et Jean-Marie GARCIA ; ; 54 page. Olivier BRUN et Jean-Marie GARCIA ; ; 48 page. Lien : uteurs.php3 Equipements réseau - Routeur uteurs.php3 18