Network virtualization: Dealing with multiple infrastructure providers

In this paper, we present some interesting issues of resource allocation in network virtualization. We also propose RAiNV, a resource allocation framework to handle those issues. Sharing of resources is in the heart of network virtualization. The key idea of network virtualization is to replace conventional Internet service provider (ISP) with two separate business entities: infrastructure providers (InP) and service providers (SP). The InPs are the owners of resources. They are responsible for maintaining a certain level of quality of service (QoS) at the physical layer. The SPs lease resources from InPs. They offer various services to end users. It is more realistic to think about a scenario with multiple InPs and multiple SPs. A single service provider (SP) can integrate resources from multiple InPs. Similarly, a single InP can distribute resources to multiple SPs. As a result, optimal resource sharing becomes a challenging task. Resource allocation covers all the virtual network (VN) provisioning matters. Major parts include resource advertisement, request, negotiation, etc. The RAiNV aims to ease dealing with multiple InPs. Its performance is evaluated using obtained numerical results through simulations.

I. Introduction

The existing Internet infrastructure is not able to meet future business demands. It was originally designed to support best-effort (BE) class of traffic. Nowadays, multiple classes of traffic are supported over the Internet. Their quality of service (QoS) requirements are different from BE class. The main challenge of the future Internet will be to ensure guaranteed QoS. Network virtualization is a way of overcoming the limitations of the Internet. It introduces a paradigm of future Internetworking. In network virtualization, an Internet service provider (ISP) is replaced by two separate business entities: infrastructure provider (InP) and service provider (SP) [1]–[2]. An InP owns a substrate network, which consists of physical nodes and links. These nodes and links are the physical resources to be virtualized. An InP is responsible to maintain a certain level of QoS at the physical layer. It virtualizes its resources and leases them to SPs. A SP leases virtual resources from InPs. These resources are virtual nodes and links that form a virtual network (VN). The SP installs its customized protocols to the VN. It offers various services to end users. Therefore, at least three types of players appear in the business models of network virtualization: InP, SP, and end users. Early concepts of VNs were confined within physically separated but logically connected networks. This kind of VNs includes virtual local area network (VLAN), virtual private network (VPN), overlay networks, etc. Their accessibility is limited within certain layers of the existing Internet. Performance bottlenecks are observed due to limited accessibility. In contrast, network virtualization introduces VNs that can be physically connected but logically separated. It allows VNs to have full access to all the layers between physical and application layer.