A Constrained Shortest Path Scheme for Virtual Network Service Management

TL;DR

This paper introduces a new exact algorithm called Neighborhoods Method for constrained shortest path problems, improving scalability and efficiency in virtual network service management across large networks.

Contribution

The paper presents the Neighborhoods Method, a novel quadratic speed-up algorithm for constrained shortest paths, enabling scalable virtual network service management in large networks.

Findings

Leverages constrained shortest paths to improve network utilization by up to 50%.

The Neighborhoods Method outperforms existing solutions by an order of magnitude in speed.

Practical validation through a real-world SDN controller implementation.

Abstract

Virtual network services that span multiple data centers are important to support emerging data-intensive applications in fields such as bioinformatics and retail analytics. Successful virtual network service composition and maintenance requires flexible and scalable 'constrained shortest path management' both in the management plane for virtual network embedding (VNE) or network function virtualization service chaining (NFV-SC), as well as in the data plane for traffic engineering (TE). In this paper, we show analytically and empirically that leveraging constrained shortest paths within recent VNE, NFV-SC and TE algorithms can lead to network utilization gains (of up to 50%) and higher energy efficiency. The management of complex VNE, NFV-SC and TE algorithms can be, however, intractable for large scale substrate networks due to the NP-hardness of the constrained shortest path problem. To address such scalability challenges, we propose a novel, exact constrained shortest path algorithm viz., 'Neighborhoods Method' (NM). Our NM uses novel search space reduction techniques and has a theoretical quadratic speed-up making it practically faster (by an order of magnitude) than recent branch-and-bound exhaustive search solutions. Finally, we detail our NM-based SDN controller implementation in a real-world testbed to further validate practical NM benefits for virtual network services.