A Walk in the Clouds: Routing Through VNFs on Bidirected Networks

  • Klaus-Tycho Foerster
  • Mahmoud ParhamEmail author
  • Stefan Schmid
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10739)


The virtualization of network functions enables innovative new network services which can be deployed quickly and at low cost on (distributed) cloud computing infrastructure. This paper initiates the algorithmic study of the fundamental underlying problem of how to efficiently route traffic through a given set of Virtualized Network Functions (VNFs). We are given a link-capacitated network \(G=(V,E)\), a source-destination pair \((s,t)\in V^2\) and a set of waypoints \(\mathscr {W} \subset V\) (the VNFs). In particular, we consider the practically relevant but rarely studied case of bidirected networks. The objective is to find a (shortest) route from s to t such that all waypoints are visited. We show that the problem features interesting connections to classic combinatorial problems, present different algorithms, and derive hardness results.



Klaus-Tycho Foerster is supported by VILLUM FONDEN project ReNet and Mahmoud Parham by AAU’s PreLytics project.


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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Aalborg UniversityAalborgDenmark

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