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Virtual network functions bring potential with some risk

Virtual network functions are the magic behind NFV. They bring software capability to routing, mobile core, security and more. But they're not without implementation challenges.

Virtual network functions (VNFs) are the crown jewels of NFV. They provide network functionality, once only found...

in hardware, across a wide range of applications, including routing, CPE, mobile core, IMS, CDN, video, security, policy, and many more.

But virtualizing network functions requires combined application, orchestration, and infrastructure software that can be challenging to integrate and tune.

Communications Service Providers (CSPs) will need to start by picking the right partners to provide NFV implementation. There are also some network environments that are better than others when it comes to starting with VNF deployment.

Picking the right partner

CSPs must begin with evaluating partners to deliver NFV applications. There are a number of VNF partner options including:

  • Leading network equipment providers (NEPs): CSPs traditionally have sourced network infrastructure from leading NEPs, including Ericsson, Cisco, Huawei, Alcatel-Lucent, Nokia, and Juniper. All of these top NEPs have various strategies to help their customers migrate (gradually) to increasingly virtual, software-based architectures.
  • Leading IT suppliers: Leading IT suppliers, such as HP, Red Hat and DELL have combined their expertise in cloud and virtual data center deployment with network/telecom software to deliver a "complete" NFV solution. IT suppliers enhance their NFV portfolio with partnerships with selected NEPs and NFV independent software vendors (ISVs).
  • NFV ISVs: A wealth of new and existing suppliers have introduced virtualized software as options for VNF deployments. CSPs can pick and choose the best software/supplier that meets their application requirements. Deployment of open source network software is also an option. This can include OpenStack, OpenDaylight, and other NFV-specific offerings. In this case, the CSP (perhaps with a professional services partner) is responsible for testing and integration of the various software components.

Notable NFV ISVs include:

  • Affirmed Networks (mobile core)
  • Brocade (routing)
  • Connectem (mobile core)
  • Cyan (orchestration)
  • Edgewater (Session Border Control)
  • Genband (IMS)
  • Metaswitch (IMS)
  • Overture (orchestration)

Challenges in implementing virtual network functions

CSPs face a number of potential challenges and risks when implementing VNFs.

It's risky to software to scale to millions of users the way hardware can. What's more, CSPs must learn new management and orchestration tools, and establish reliable links between the virtual and physical network elements.

They face additional challenges as they integrate the VNFs with their existing, often complex operational, support and billing back-office systems. From a cost perspective, CSPs must manage the trade-offs of expected lower capital costs with the potential for higher operational costs as their staff must master new tools to operate and manage virtual networks.

Choosing the right scenario for virtual network function implementation

The likely scenarios for initial VNF implementation are in situations that can reduce the risk for CSP operations staff. These include:

  • Greenfield deployments: New deployment of networks in geographic regions in which the CSPs has limited or no physical network deployment.
  • New service offerings. CSPs looking to rapidly and cost effectively introduce new services -- for example, cable MSOs offering wireless services or CSPs expanding their offerings to small businesses.
  • Virtual Network Operations: New entrants offering telecom services and possibly partnering with existing CSPs that have physical networks.

Recommendations for CSPs

The migration to virtual networks will be a five-to-10-year journey for most incumbent CSPs. Smaller operators or those offering new telecom services may implement NFV in a faster time frame. CSPs will have to manage the risk of introducing new VNF technology to their existing highly reliable networks. In order to be successful, CSPs need to carefully evaluate and test specific NFV technology, pick applications and types of deployments that have the best chance of success, and work with partners who can deliver reliable NFV deployments.

About the author:
Lee Doyle is principal analyst at Doyle Research, which provides targeted analysis on the evolution of intelligent networks: SDN, Opex and COTS. Doyle has over 28 years' experience analyzing the IT, network and telecom markets. For more information, please see 
his website and email him at[email protected].

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This was last published in December 2014

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