(Literally) above the clouds: virtualizing the network over multiple clouds

TL;DR

This paper proposes a novel network virtualization architecture that spans multiple cloud providers and private facilities, enabling flexible, isolated, and cost-effective virtual networks across heterogeneous cloud environments.

Contribution

It introduces a new network layer above cloud hypervisors to support multi-cloud virtual networks, extending SDN-based solutions beyond single datacenter environments.

Findings

Prototype implementation demonstrates feasibility

Supports cross-cloud network control and isolation

Potential for cost reduction and compliance

Abstract

Recent SDN-based solutions give cloud providers the opportunity to extend their "as-a-service" model with the offer of complete network virtualization. They provide tenants with the freedom to specify the network topologies and addressing schemes of their choosing, while guaranteeing the required level of isolation among them. These platforms, however, have been targeting the datacenter of a single cloud provider with full control over the infrastructure. This paper extends this concept further by supporting the creation of virtual networks that span across several datacenters, which may belong to distinct cloud providers, while including private facilities owned by the tenant. In order to achieve this, we introduce a new network layer above the existing cloud hypervisors, affording the necessary level of control over the communications while hiding the heterogeneity of the clouds. The benefits of this approach are various, such as enabling finer decisions on where to place the virtual machines (e.g., to fulfill legal requirements), avoiding single points of failure, and potentially decreasing costs. Although our focus in the paper is on architecture design, we also present experimental results of a first prototype of the proposed solution.