TABLE OF CONTENTS J'ai r v la nuit verte aux neiges blouies
Baiser montant aux yeux des neiges avec lenteurs
La circulation des s ves inou es
Et l' veil jaune et bleu des phosphores chanteurs
On innocent nights, I'd dream of brilliant snows
Slowly mounting kiss to the rolling seas
As though driven by rising sap
And the blue and yellow awakening of the singing phosphorescence
Arthur Rimbaud, Le Bateau Ivre (The Drunken Ship)
In this chapter we want to discuss optimal routing of the traffic, so as to maximize the margin of an SMS interworking network. It is assumed that the reader knows only the vocabulary of graph theory and network flows [1, 2]. For Section 10.6, some background in mathematical programming theory [2, 3] is required.
Let us consider the graph of Figure 10.1, where S is the set of customers who want to send SMS to all the mobile networks S'. As the basis of a crude or sophisticated optimization method, we want first to have an algorithm that computes all the paths from every origin (customers sending SMS) to every destination [various mobile networks (SMS-MT) or content providers]. In Figure 10.1, the indices i, j, k denote the various nodes, also called routers, of an SMS interworking network. It shows that several paths, using different nodes, can be used for the traffic demand from a customer s ? S
