The Network Functions Virtualization, a different kind of animal

If you are involved somehow in the telecom’s industry, you should know the buzz that Network Functions Virtualization (NFV), and its parent trend Software Defined Networks (SDN), are having in both vendors and operators. This in part because the NFV trend was originally encouraged by the main operators of the world themselves, with October 2012’s whitepaper (here), on an exercise where they seemed to explain what they wanted to see in their networks in the future. Which is in other words like commenting what type of technology they wanted to buy, or wanted to be sell on, for having that well-known list of NFV/SDN advantages in the future (i.e. reduced CAPEX/OPEX, simpler and standard networks, shared resources, faster services, etc.).


The excitement and kind of “shark behaviour” of all the involved can be seen by the fact that more than 100 companies or organizations are directly involved in the NFV standardization, via the ETSI (here), without mentioning those involved in the SDN standardization, via the ONF. Being realistic I believe these trends will not be so great in the short term, but most likely not so terrible in the long term neither, on a classical Amaras’ law fashion. The operators are simply pushing for securing the future of their business, and we know the current traditional networks will not be migrated or replaced to virtual networks in the short nor medium term, but the new ones being installed in the mid-term might be a different story depending on the NFV/SDN evolution pace.

Now what are the NFV and SDN trends after all? I remember an interview I especially liked with one of the Technical Experts for Networks Virtualization initiatives from Telefonica I+D, during the SDN World congress in Barcelona last June 2013. He made a simple explanation by saying, “Current traditional networks are like having a group of dogs and cats for pets, you must feed them and take care of them independently, each one has its own different needs, and sometimes you cannot have them together. What we (the operators) are looking to have with NFV are networks like a herd of horses or cows, where we can maintain them and work with them as a group, despite having faster horses or some dedicated to specific jobs, but sharing the same needs and therefore requiring around the same resources and skills for maintaining those”. This is an analogy that explains by itself with the fact the operators spend huge amounts of money in OPEX for the current networks. This without mentioning that any upgrade, integration, or evolution, requires huge CAPEX with its consequent increased OPEX during the nodes life cycles. Now you can imagine having a whole IMS network hosted in highly efficient and cost effective COTS hardware in a rack, with separate and automatically orchestrated virtual domains in software, dedicated for each function. Note I say function instead of node, since the idea is again simplifying the architectures, so if a SBC and a CSCF share a functionality it would only appear once in this new approach. That would represent multiple advantages compared with the traditional approach of multiple different nodes, with different hardware and software for each stage of the IMS flow, including: power consumption reduction, less signalling messages required, lower latencies, flexible and automatic scalability, and a lot less resources for maintaining the operation… among many others. Now imagine that in the core network, or in the Value Added Services (VAS), etc. So that is the operators’ panacea, and some vendors are already having some solutions thinking on that, starting with the nodes more easy to handle in the virtual world without affecting performance and reliability, like: policy & charging, firewalls, signalling routers, or some IMS network elements.

Therefore if we were to define the NFV and SDN trends in simple terms, the SDN would then be as splitting the control plane from the data plane in the networks, while NFV would be like splitting the software from the hardware; both could be implemented together, or independently, depending on the path followed and the specific needs. A third and final flavour is added to the mix with Cloud computing. Most of the industry experts believe the real gain of NFV/SDN applied to the carriers should be the same already proven in the enterprises’ data centres world, and that is having most of these architectures in the cloud. In the previous example of the IMS network, you can imagine that rack hosted by some cloud provider taking care of its capacity and maintenance on an outsourced model of SaaS, and opening a set of API’s with the operator’s services. If you are concerned about security in that approach you can even consider having that cloud hosted in your own data centre, having then a private cloud, etc.


Even when some vendors are already claiming to have carrier grade NFV/SDN solutions for the operators, I think no one has yet offered a full and solid product for this year. According to a survey from Heavy Reading this year, 32% of the respondents think the SDN will be widely adopted by 2015, and 36% think by 2016 or later (here). I would say the vendors closer to have these solutions ready for the operators are Alcatel-Lucent with the CloudBand, and Cisco with the Cisco ONE. Some groups of small vendors are also working together to offer interesting things in the near future, like the CloudNFV group (here). And some specific services oriented vendors are just offering a virtual version of the same nodes previously owned, like the Policy and Charging vendors, including: F5, Amdocs, Openet, Tekelec, etc. A report from Informa Telecoms & Media, with Juniper Networks sponsorship, states: “…operators consider mobile SDN to be a critical technology for the future of networks: Ninety-three percent of operator respondents expect SDN to be implemented in mobile within five years, and half expect it to be implemented in the next one to two years” (here).

As the momentum for NFV/SDN is building rapidly, make sure you are prepared for the new and different kind of animal in the farm.