Network Functions Virtualization (NFV) or Software Design Networking (SDN)?

By: Ahmed Banafa, Distinguished Tenured Staff | Faculty | SME | E-Learning Expert | Four-time winner of instructor of the year award

What is Network Functions Virtualization (NFV)?

Network Functions Virtualization (NFV) is a network architecture concept that proposes using IT virtualization related technologies, to virtualize entire classes of network node functions into building blocks that may be connected, or chained, together to create communication services.

Network functions Virtualization (NFV) offers a new way to design deploy and manage networking services. NFV decouples the network functions, such as network address translation (NAT), firewalling, intrusion detection, domain name service (DNS), caching, etc., from proprietary hardware appliances, so they can run in software.

It’s designed to consolidate and deliver the networking components needed to support a fully virtualized infrastructure – including virtual servers, storage and even other networks.  It utilizes standard IT virtualization technologies that run on high-volume service, switch and storage hardware to virtualize network functions. It is applicable to any data plane processing or control plane function in both wired and wireless network infrastructures.

The Benefits of NFV

Reduce CapEx: reducing the need to purchase purpose-built hardware and supporting pay-as-you-grow models to eliminate wasteful overprovisioning.

Reduce OpEX: reducing space, power and cooling requirements of equipment and simplifying the roll out and management of network services.

Accelerate Time-to-Market: reducing the time to deploy new networking services to support changing business requirements, seize new market opportunities and improve return on investment of new services.

Deliver Agility and Flexibility: quickly scale up or down services to address changing demands; support innovation by enabling services to be delivered via software on any industry-standard server hardware.

Enable Innovation: enabling organizations to create new types of applications, services and business models. 

Types of NFV

Almost any network function can be virtualized. The NFV focus in the market today includes

Virtual Switching – physical ports are connected to virtual ports on virtual servers with virtual routers using virtualized IPsec and SSL VPN gateways.

Virtualized Network Appliances – network functions that today require a dedicated box can be replaced with a virtual appliance. Examples include firewalls, web security, IPS/IDS, WAN acceleration and optimization.

Virtualized Network Services – examples here are network management applications such as traffic analysis, network monitoring tools, load balancers and accelerators.

Virtualized Applications – almost any application you can imagine. For example, there is a great deal of development today for cloud applications, such as virtualized storage and photo imaging services, to support the explosion in tablet and smartphone usage.

Which is Better – SDN or NFV?

Whereas SDN was created by researchers and data center architects, NFV was created by a consortium of service providers. Software-Defined Networking (SDN), and Network functions Virtualization (NFV), are all complementary approaches. They each offer a new way to design deploy and manage the network and its services:

SDN – separates the network’s control (brains) and forwarding (muscle) planes and provides a centralized view of the distributed network for more efficient orchestration and automation of network services.

NFV – focuses on optimizing the network services themselves. NFV decouples the network functions, such as DNS, Caching, etc., from proprietary hardware appliances, so they can run in software to accelerate service innovation and provisioning, particularly within service provider environments.

SDN and NFV each aim to advance a software-based approach to networking for more scalable, agile and innovative networks that can better align and support the overall IT objectives of the business.  It is not surprising that some common doctrines guide the development of each.

They each aim to:

Move functionality to software Use commodity servers and switches over proprietary appliances Leverage programmatic application interfaces (APIs) Support more efficient orchestration, virtualization and automation of network services

These approaches are mutually beneficial, but are not dependent on one another.  You do not need one to have the other. However, the reality is SDN makes NFV more compelling and visa-versa.  SDN contributes network automation that enables policy-based decisions to orchestrate which network traffic goes where, while NFV focuses on the services it’s supporting. The advancement of all these technologies is the key to evolving the network to keep pace with the innovations of all the people and devices its connecting.

The Future of NFV?

NFV could also be extended to non-connectivity features of the network. Probably the most relevant of these use cases is context-aware networking or the ability to make performance and provisioning decisions based on location, user activity and even social context. If users are busy, they don't have to receive application access. Or they can receive varying levels of access depending on the type of application they need.

NFV is about function hosting, and there are many ways to host functions—from appliances to dedicated servers, through virtualization and via the cloud. But NFV will create a framework for deploying complex applications and operating them with high reliability and low operational expenditure costs. This will allow operators to price even complex contextual applications at levels that are consistent with broad adoption and still make a satisfactory profit from their investment. It will also allow operators to bring new services to market faster, accelerating revenue realization and encouraging investment.

References

http://www.6wind.com/software-defined-networking/sdn-nfv-primer/http://www.tmcnet.com/tmc/whitepapers/documents/whitepapers/2013/9377-network-functions-virtualization-challenges-solutions.pdfhttp://www.sdncentral.com/why-sdn-software-defined-networking-or-nfv-network-functions-virtualization-now/http://www.sdncentral.com/technology/nfv-and-sdn-whats-the-difference/2013/03/http://www.sdncentral.com/whats-network-functions-virtualization-nfv/http://www.sdncentral.com/which-is-better-sdn-or-nfv/http://www.tmcnet.com/tmc/whitepapers/documents/whitepapers/2013/9377-network-functions-virtualization-challenges-solutions.pdfhttp://en.wikipedia.org/wiki/Network_Functions_Virtualizationhttp://searchsdn.techtarget.com/feature/Is-service-agility-the-payoff-in-network-functions-virtualization