For the first time in the literature, the paper considers computational aspects of concave cost virtual private network design problems. It introduces careful bound tightening mechanisms and computationally demonstrate how such bound tightening could impressively improve convex relaxations of the problem. It turns out that, incorporating such bound tightening with a general solution approach co...

The VPN Tree Routing Conjecture states that there always exists an optimal solution to the symmetric Virtual Private Network Design (sVPND) problem where the paths between all terminals form a tree. Only recently, Hurkens, Keijsper, and Stougie gave a proof of this conjecture for the special case of ring networks. Their proof is based on a dual pair of linear programs and is somewhat involved. ...

As the most basic cloud service model, Infrastructure as a Service (IaaS) has been widely used for serving the evergrowing computing demand due to the prevalence of the cloud. Using pools of hypervisors within the cloud, IaaS can support a large number of Virtual Machines (VMs) and scale services in a highly dynamic manner. However, it is well-known that the VMs in IaaS are vulnerable to co-res...

The signaling protocols used to establish point-to-point pseudowires include type-length-value (TLV) fields that identify pseudowire endpoints called attachment individual identifiers (AIIs). This document defines AII structures in the form of new AII TLV fields that support AII aggregation for improved scalability and Virtual Private Network (VPN) auto-discovery. It is envisioned that this wou...

This paper describes VServ, a prototype architecture for a virtual private network (VPN) service, which builds and manages VPNs on demand. It allows each VPN to have guaranteed resources and customized control, and supports a highly dynamic VPN service where creation and modification operations can take place on fast timescales. These features are contingent on the automated establishment and m...

In ATM networks, VPCs (Virtual Path Connections) could be setup permanently or semi-permanently by network administrators to form a virtual private network or temporarily by applications to group several VCCs (Virtual Channel Connections) of users. Virtual path management is of great importance in maintaining ATM network service quality. In this paper, we propose our heuristics for three proble...

Cyber threats become more and more pervasive on the Internet and on distributed/decentralized systems. In order to secure communication over these infrastructures and respond to mobility constraint, a new class of Virtual Private Networks (VPN), which support both security and mobility, has emerged in the course of last years. Mobile Virtual Private Networks, called mobile VPN, provide not only...