Abstract

International audience; Mobility and security are major features for both current and future network infrastructures. Nevertheless, the integration of mobility in traditional virtual private networks is difficult due to the costs of re-establishing broken secure tunnels and restarting broken connections. Besides session recovery costs, renegotiation steps also present inherent vulnerabilities. In order to address these issues, we propose a new distributed mobile VPN system called SEcured MObile Session (SEMOS). Based upon our CLOAK peer-to-peer overlay architecture, SEMOS provides security services to the application layer connections of mobile users. Secure and resilient sessions allow user connections to survive network failures as opposed to regular transport layer secured connections used by traditional VPN protocols. Document type: Part of book or chapter of book

Abstract

International audience; Virtual Private Networks (VPNs) are overlay networks established on top of a public network backbone with the goal of providing a low cost but secure network solution. The allocation of bandwidth for VPN tunnels to meet the requirements specified by customers is an important traffic engineering research issue. This paper addresses the general problem of computing a constrained VPN with a tree topology, and having optimum bandwidth allocation. This is a hard combinatorial optimization problem [1]. This issue was studied first by different resource allocation methods [2] and next was studied by general optimization methods [3]. In this paper, we present integer programming formulations (IPFs) assuming a hose as well as a pipe workload models. Earlier work [2] showed that the hose model results in VPN trees over provisioned by a factor of 2-to-3. Extensive simulations using test networks and their corresponding hose workloads, generated with Brite [4] show that our exact methods produce VPN tree solutions with a bandwidth over-provisioning factor as low as 1.6, and never exceeds a factor of 2, compared to solutions obtained using a pipe workload.