Challenges in Resource Allocation in Network Virtualization

Virtualization promises to overcome the weaknesses of the current Internet and to act as a torch bearer technology for enabling innovative network architectures. However, a fundamental problem in instantiation of Virtual Networks (VNs) is an optimal allocation of resources offered by a physical IP network. In order to solve this NP-hard problem, heuristics have been proposed in literature. This paper attempts to concisely present some of the major techniques for resource allocation in VNs. System level models have been employed to better understand the resource allocation process. These models can be useful for the design of efficient systems for instantiation of VNs. Relatedly, resource allocation techniques in some popular test-beds have been also briefly presented. Major contributions of this paper include: a concise survey of the latest techniques for resource allocation in VNs, proposing a new objective function for mapping of VNs, a system level description/analysis of resource allocation problems and identifying some important research challenges.