Optimizing primary and backup SDN controllers' placement resilient to node-targeted attacks

Abstract

In Software Defined Networks (SDNs), a number of controllers are placed in a given data plane network. In a standard logically centralized control plane, each controller acts simultaneously as a primary controller for some switches and as a backup controller for other switches, and the controller placements must meet given switch-controller (SC) and controllercontroller (CC) delay bounds. Then, the SDN should be resilient to network disruptions such as node-targeted attacks. To improve the SDN resilience to this kind of disruptions, we assume that some controllers are deployed only as backup controllers so that they take over the functions of primary controllers only in case of disruption. We propose an optimization model that solves a relevant primary and backup controller placement problem, where a minimum number of primary controllers minimizing the maximum SC delay is first established, and then a joint primary and backup controller placement maximizing the resilience of the SDN against a list of the most dangerous node-targeted attacks is determined. A numerical study illustrating the merits of the proposed optimization methodology is presented.

Maximizing SDN resilience to node‐targeted attacks through joint optimization of the primary and backup controllers placements

“…Finally, we note that the material presented in this paper is a far‐reaching extension of the research ideas discussed in our conference papers [13] and [17]. In the current paper we extend, improve and compare the optimization models introduced therein, and thoroughly examine both the problem and the models by means of a broad, comprehensive numerical study.…”

“…As far as we know, our conference paper [13] is the first work dealing with joint optimization of primary and backup controllers placements. For that purpose, an optimization model that maximizes network resilience against a given list of node‐targeted attacks is proposed.…”

“…In short, CPP consists in finding a placement of primary controllers and a placement of backup controllers that jointly maximize the assumed network availability measure $$$ \mathcal{M}\left(\mathcal{A}\right) $$$ (see (3) and (4)) for a given set of attacks $$$ \mathcal{A} $$$. The formulations presented below are original as the so posed problem has, to the best of our knowledge, not been dealt with in the literature so far (except for our conference papers [13] and [17]).…”

Min–max optimization of node‐targeted attacks in service networks

“…Since controller placement optimization is not the main concern of this article, we only mention here that although this topic is dealt with in numerous surveys (for example, [7,18,32]) and numerous research papers (for example, [13,22,25]), most of the work described there does not consider resilience to attacks, and is devoted to optimizing controllers placements with respect to such measures as controller-to-controller delay and (service) node-to-controller delay. Controller placement problems directly related to the one formulated in this article (CPOP, Section 3.2) are considered in such papers as [27][28][29], and also in more recent papers [3,20,24]. However, all these papers assume fixed lists of attacks, pre-calculated without taking into account possible locations of controllers, while in this article, and in [33], the problem is to find a placement of controllers that maximizes the number of surviving service nodes, no matter what set (of a given size) of node locations is attacked.…”