Network routing control with G-networks

The aim of this paper is to detail a control scheme for packet computer networks whose purpose is to minimise a quality-of-service oriented performance metric by re-routing the traffic. The model is based on G-networks with triggered customer movement to represent traffic re-routing, and on a gradient descent based optimisation algorithm. The model and the algorithm are presented and we show that the gradient descent algorithm is of computational complexity O ( N 3 ) where N is the number of nodes in the packet network. Via the use of multiple classes of normal traffic and multiple classes of triggers, our approach allows one not only to evaluate the effect of the control, but also to incorporate the overhead that the control traffic will induce, and the consequences of the delays or possible losses of the control traffic. Similarly, these effects will naturally be incorporated when one considers both the impact of the control traffic on the cost function, and the details of this control traffic in the control algorithm itself.