by Bob Natale
Network Services Virtualization (NSV) is an emergent capability, a transformation in network service delivery and consumption capabilities rising from the optimal integration of enabling technologies that collectively underpin the revolution in network virtualization. The set of NSV-enabling technologies – summarized in the listing in Figure 1 (red font) – centers on Network Functions Virtualization (NFV) and Software-Defined Networking (SDN), and includes other technologies necessary for a fully functional NSV solution.
A fully functional NSV solution promises major benefits to service providers and consumers in business value and mission outcomes. These benefits derive primarily from gains in consolidation, automation, and agility that emerge from the optimal integration of the enabling technologies. Optimal integration results in a coherent solution – i.e., a solution characterized by completeness, consistency, and efficiency.
To design a coherent solution from such a large set of new interrelated technologies, and then develop, deploy, operate, and use that solution in demanding business and mission environments presents significant challenges. The three primary challenges involve understanding the problem and solution spaces, satisfying the coherency criteria for the candidate solution, and effectively communicating the solution to the affected stakeholders and decision-makers to ensure they can implement and derive maximum value from it.
Solution architects produce solution architectures to address those challenges in the concept development stage of the systems engineering lifecycle . A solution architecture outlines a coherent integration of solution components and corresponding migration paths that show the evolution of a system from a baseline state to a target state. For NSV solution architecture, the baseline state is the set of enabling technologies listed in Figure 1; the target state is a coherent integration of those technologies. Figure 2 provides a possible visualization of the target state for NSV.
The basic purposes and high-level interrelationships of the enabling technology components for NSV are identified in the contextual information (black and blue font) in Figure 1. A more detailed explanation of the inter-component relationships is beyond the scope of this blog. Explaining the path from the baseline state to the target state in terms of component relationships, however, is not sufficient for stakeholder and decision-maker purposes. The value proposition must be overlaid on that target state to illustrate how the promised benefits relate to the components as organized in target state solution. Figure 3 captures such an overlay for the NSV target state.
When coupled with a background understanding (beyond the scope of this blog) of the purposes for the individual technologies listed in Figure 1 and the basic relationships among them as outlined in Figure 2, the visualization in Figure 3 conveys an understanding that NSV delivers service providers return on investment (ROI), and service consumers value in the following major ways:
- – NFV promotes consolidation (yellow dashed-line triangle area) by eliminating (or reducing) dedicated purpose-built hardware devices by replacing them with software appliances that can execute as Virtual Network Functions (VNFs) on commodity hardware, possibly in cloud IaaS environments.
- – SDN promotes automation (blue dashed-line triangle area) by normalizing the control plane via standardized protocols, data models, and “white box” controllers.
- – iPBM and SFC/SFP promote agility (green dashed-line triangle area) by enabling standardized high-level policy expressions to govern network and service behavior, and personalized and mission-specific customization of network service offerings.
- – MANO promotes mission-specific effectiveness, efficiency, and affordability (conjunction in the brown dashed-line triangle area); this is achieved through a productive, reliable, and secure orchestration and management of the service delivery platform and virtual network environment, which is enabled by the NSV constituent technologies.
The foregoing brief outline of the role of solution architecture in bringing the NSV vision to fruition is just a start. It is an attempt to whet the reader’s appetite for a broader and deeper understanding of the contributions that solution architects can make in realizing an optimal coherent implementation model for NSV that delivers on its promised benefits over pre-NSV virtualized network services.
The tutorials in the ONUG Academy (May 12) and the technical sessions in the ONUG Spring 2015 Conference (May 13 and 14) will offer attendees excellent opportunities for progress on that broader and deeper understanding of NSV.
 MITRE, The Evolution of Systems Engineering, http://www.mitre.org/publications/systems-engineering-guide/systems-engineering-guide/the-evolution-of-systems, accessed April 14, 2015.
Chief Engineer, Joint NetOps & Cyber Defense