The quiet progress of Network Functions Virtualisation
Network Functions Virtualisation (NFV) is a term less often heard these days.
Yet the technology framework that kickstarted a decade of network transformation by the telecom operators continues to progress.
The working body specifying NFV, the European Telecommunications Standards Institute’s (ETSI) Industry Specification Group (ISG) Network Functions Virtualisation (NFV), is working on the latest releases of the architecture.
The releases add AI and machine learning, intent-based management, power savings, and virtual radio access network (VRAN) support.
ETSI is also shortening the time between NFV releases.
“NFV is quite a simple concept but turning the concept into reality in service providers’ networks is challenging,” says Bruno Chatras, ETSI’s ISG NFV Chairman and senior standardisation manager at Orange Innovation. “There are many hidden issues, and the more you deploy NFV solutions, the more issues you find that need to be addressed via standardisation.”
NFV’s goal
Thirteen leading telecom operators published a decade ago the ETSI NFV White Paper.
The operators were frustrated. They saw how the IT industry and hyperscalers innovated using software running on servers while they had cumbersome networks that couldn’t take advantage of new opportunities.
Each network service introduced by an operator required specialised kit that had to be housed, powered, and maintained by skilled staff that were increasingly hard to find. And any service upgrade required the equipment vendor to write a new release, a time-consuming, costly process.
The telcos viewed NFV as a way of turning network functions into software. Such network functions – constituents of services – could then be combined and deployed.
“We believe Network Functions Virtualisation is applicable to any data plane packet processing and control plane function in fixed and mobile network infrastructures,” claimed the authors in the seminal NFV White Paper.
A decade on
Virtual network functions (VNFs) now run across the network, and the transformation buzz has moved from NFV to such topics as 5G, Open RAN, automation and cloud-native.
Yet NFV changed the operators’ practices by introducing virtualisation, disaggregation, and open software practices.
A decade of network transformation has given rise to new challenges while technologies such as 5G and Open RAN have emerged.
Meanwhile, the hyperscalers and cloud have advanced significantly in the last decade.
“When we coined the term NFV in the summer of 2012, we never expected the cloud technologies we wanted to leverage to stand still,” says Don Clarke, one of the BT authors of the original White Paper. “Indeed, that was the point.”
NFV releases
The ISG NFV’s work began with a study to confirm NFV’s feasibility, and the definition of the NFV architecture and terminology.
Release 2 tackled interoperability. The working group specified application programming interfaces (APIs) between the NFV management and orchestration (MANO) functions using REST interfaces, and also added ‘descriptors’.
A VNF descriptor is a file that contains the information needed by the VNFM, an NFV-MANO functional block, to deploy and manage a VNF.
Release 3, whose technical content is now complete, added a policy framework. Policy rules given to the NFV orchestrator determine where best to place the VNFs in a distributed infrastructure.
Other features include VNF snapshotting for troubleshooting and MANO functions to manage the VNFs and network services.
Release 3 also addressed multi-site deployment. “If you have two VNFs, one is in a data centre in Paris, and another in a data centre in southern France, interconnected via a wide area network, how does that work?” says Chatras.
The implementation of a VNF implemented using containers was always part of the NFV vision, says ETSI.
Initial specifications concentrated on virtual machines, but Release 3 marked NFV’s first container VNF work.
Release 4 and 5
The ISG NFV working group is now working on Releases 4 and 5 in parallel.
Each new release item starts with a study phase and, based on the result, is turned into specifications.
The study phase is now limited to six months to speed up the NFV releases. The project is earmarked for a later release if the work takes longer than expected.
Two additions in NFV Release 4 are container management frameworks such as Kubernetes, a well-advanced project, and network automation: adding AI and machine learning and intent management techniques.
Network automation
NFV MANO functions already provide automation using policy rules.
“Here, we are going a step further; we are adding a management data analytics function to help the NFV orchestrator make decisions,” says Chatras. “Similarly, we are adding an intent management function above the NFV orchestrator to simplify interfacing to the operations support systems (OSS).”
Intent management is an essential element of the operators’ goal of end-to-end network automation.
Without intent management, if the OSS wants to deploy a network service, it sends a detailed request using a REST API to the NFV orchestrator on how to proceed. For example, the OSS details the VNFs needed for the network service, their interconnections, the bandwidth required, and whether IPv4 or IPv6 is used.
“With an intent-based approach, that request sent to the intent management function will be simpler,” says Chatras. “It will just set out the network service the operator wants, and the intent management function will derive the technical details.”
The intent management function, in effect, knows what is technically possible and what VNFs are available to do the work.
The work on intent management and management data analytics has just started.
“We have spent quite a lot of time on a study phase to identify what is feasible,” says Chatras.
Release 5 work started a year ago with the ETSI group asking its members what was needed.
The aim is to consolidate and close functional gaps identified by the industry. But two features are being added: Green NFV and support for VRAN.
Green NFV and VRAN
Energy efficiency was one of the expected benefits listed in the original White Paper.
ETSI has a Technical Committee for Environmental Engineering (TC EE) with a working group to reduce energy consumption in telecommunications.
The energy-saving work of Release 5 is solely for NFV, one small factor in the overall picture, says Chatras.
Just using the orchestration capabilities of NFV can reduce energy costs.
“You can consolidate workloads on fewer servers during off-peak hours,” says Chatras. “You can also optimise the location of the VNF where the cost of energy happens to be lower at that time.“
Release 5 goes deeper by controlling the energy consumption of a VNF dynamically using the power management features of servers.
The server can change the CPU’s clock frequency. Release 5 will address whether the VNF management or orchestration does this. There is also a tradeoff between lowering the clock speed and maintaining acceptable performance.
“So, many things to study,” says Chatras.
The Green NFV study will provide guidelines for designing an energy-efficient VNF by reducing execution time and memory consumption and whether hardware accelerators are used, depending on the processor available.
“We are collecting use cases of what operators would like to do, and we hope that we can complete that by mid-2022,” says Chatras.
The VRAN work involves checking the work done in the O-RAN Alliance to verify whether the NFV framework supports all the requirements. If not, the group will evaluate proposed solutions before changing specifications.
“We are doing that because we heard from various people that things are missing in the ETSI ISG NFV specifications to support VRAN properly,” says Chatras.
Is the bulk of the NFV work already done? Chatras thinks before answering: “It is hard to say.”
The overall ecosystem is evolving, and NFV must remain aligned, he says, and this creates work.
The group will complete the study phases of Green NFV and NFV for VRAN this summer before starting the specification work.
NFV deployments
ETSI ISG NFV has a group known as the Network Operator Council, comprising operators only.
The group creates occasional surveys to assess where NFV technology is being used.
“What we see is confidential, but roughly there are NFV deployments across nearly all network segments: mobile core, fixed networks, RAN and enterprise customer premise equipment,” says Chatras.
VNFs to CNFs
Now there is a broad industry interest in cloud-native network functions. But the ISG NFV group believes that there is a general misconception regarding NFV.
“In ETSI, we do not consider that cloud-native network functions are something different from VNFs,” says Chatras. “For us, a cloud-native function is a VNF with a particular software design, which happens to be cloud-native, and which in most cases is hosted in containers.”
The NFV framework’s goal, says ETSI, is to deliver a generic solution to manage network functions regardless of the technology used to deploy them.
Chatras is not surprised that the NFV is less mentioned: NFV is 10-years-old and it happens to many technologies as they mature. But from a technical standpoint, the specifications being developed by ETSI NFV comply with the cloud model.
Most operators will admit that NFV has proved very complex to deploy.
Running VNFs on third-party infrastructure is complicated, says Chatras. That will not change whether an NFV specification is used or something else based on Kubernetes.
Chatras is also candid about the overall progress of network transformation. “Is it all happening sufficiently rapidly? Of course, the answer is no,” he says.
Network transformation has many elements, not just standards. The standardisation work is doing its part; whenever an issue arises, it is tackled.
“The hallmark of good standardisation is that it evolves to accommodate unexpected twists and turns of technology evolution,” agrees Clarke. “We have seen the growth of open source and so-called cloud-native technologies; ETSI NFV has adapted accordingly and figured out new and exciting possibilities.”
Many issues remain for the operators: skills transformation, organisational change, and each determining what it means to become a ‘digital’ service provider.
In other words, the difficulties of network transformation will not magically disappear, however elegantly the network is architected as it transitions increasingly to software and cloud.
Can a think tank tackle telecoms innovation deficit?
The Telecom Ecosystem Group (TEG) will publish shortly its final paper that concludes two years of industry discussion on ways to spur innovation in telecommunications.
The paper, entitled Addressing the Telecom Innovation Deficit, says telcos have lost much of their influence in shaping the technologies on which they depend.
“They have become ageing monocultures; disruptive innovators have left the industry and innovation is outsourced,” says the report.
The TEG has held three colloquiums and numerous discussion groups soliciting views from experienced individuals across the industry during the two years.
The latest paper names eight authors but many more contributed to the document and its recommendations.
Network transformation
Don Clarke, formerly of BT and CableLabs, is one of the authors of the latest paper. He also co-authored ETSI’s Network Functions Virtualisation (NFV) paper that kickstarted the telcos’ network transformation strategies of the last decade.
Many of the changes sought in the original NFV paper have come to pass.
Networking functions now run as software and no longer require custom platforms. To do that, the operators have embraced open interfaces that allow disaggregated designs to tackle vendor lock-in. The telcos have also adopted open-source software practices and spurred the development of white boxes to expand equipment choice.
Yet the TEG paper laments the industry’s continued reliance on large vendors while smaller telecom vendors – seen as vital to generate much-needed competition and innovation – struggle to get a look-in.
The telecom ecosystem
The TEG segments the telecommunications ecosystem into three domains (see diagram).
The large-scale data centre players are the digital services providers (top layer). In this domain, innovation and competition are greatest.
The digital network provider domain (middle layer) is served by a variety of players, notably the cloud providers, while it is the telcos that dominate the physical infrastructure provider domain.
At this bottom layer, competition is low and overall investment in infrastructure is inadequate. A third of the world’s population still has no access to the internet, notes the report.
The telcos should also be exploiting the synergies between the domains, says the TEG, yet struggle to do so. But more than that, the telcos can be a barrier.
Clarke cites the emerging metaverse that will support immersive virtual worlds as an example.
Metaverse
The “Metaverse” is a concept being promoted by the likes of Meta and Microsoft and has been picked up by the telcos, as evident at this week’s MWC Barcelona 22 show.
Meta’s Mark Zuckerberg recently encouraged his staff to focus on long-term thinking as the company transitions to become a metaverse player. “We should take on the challenges that will be the most impactful, even if the full results won’t be seen for years,” he said.
Telcos should be thinking about how to create a network that enables the metaverse, given the data for rendering metaverse environments will come through the telecom network, says Clarke.
“The real innovation will come when you try and understand the needs of the metaverse in terms of networking, and then you get into the telco game,” he says.
Any concentration of metaverse users will generate a data demand likely to exhaust the network capacity available.
“Telcos will say, ‘We aren’t upgrading capacity because we are not getting a return,’ and then metaverse innovation will be slowed down,” says Clarke.
He says much of the innovation needed for the metaverse will be in the network and telcos need to understand the opportunities for them. “The key is what role will the telcos have, not in dollars but network capability, then you start to see where the innovation needs to be done.”
The challenge is that the telcos can’t see beyond their immediate operational challenges, says Clarke: “Anything new creates more operational challenges and therefore needs to be rejected because they don’t have the resources to do anything meaningful.”
He stresses he is full of admiration for telcos’ operations staff: “They know their game.” But in an environment where operational challenges are avoided, innovation is less important.
TEG’s action plan
TEG’s report lists direct actions telcos can take regarding innovation. These cover funding, innovation processes, procurement and increasing competition.
Many of the proposals are designed to help smaller vendors overcome the challenges they face in telecoms. TEG views small vendors and start-ups as vital for the industry to increase competition and innovation.
Under the funding category, TEG wants telcos to allocate a least 5 per cent of procurement to start-ups and small vendors. The group also calls for investment funds to be set up that back infrastructure and middleware vendors, not just over-the-top start-ups.
For innovation, it wants greater disaggregation so as to steer away from monolithic solutions. The group also wants commitments to fast lab-to-field trials (a year) and shorter deployment cycles (two years maximum) of new technologies.
Competition will require a rethink regarding small vendors. At present, all the advantages are with the large vendors. It lists six measures how telcos can help small vendors win business, one being to stop forcing them to partner with large vendors. The TEG wants telcos to ensure enough personnel that small vendors get all the “airtime” they need with the telcos.
Lastly, concerning procurement, telcos can do much more.
One suggestion is to stop sending small vendors large, complex request for proposals (RFPs) that they must respond to in short timescales; small vendors can’t compete with the large RFP teams available to the large vendors.
Also, telcos should stop their harsh negotiating terms such as a 30 per cent additional discount. Such demands can hobble a small vendor.
Innovation
“Innovation comes from left field and if you try to direct it with a telco mindset, you miss it,” says Clarke. “Telcos think they know what ‘good’ looks like when it comes to innovation, but they don’t because they come at it from a monoculture mindset.”
He said that in the TEG discussions, the idea of incubators for start-ups was mentioned. “We have all done incubators,” he says. But success has been limited for the reasons cited above.
He also laments the lack of visionaries in the telecom industry.
A monoculture organisation rejects such individuals. “Telcos don’t like visionaries because culturally they are annoying and they make their life harder,” he says. “Disruptors have left the industry.”
Prospects
The authors are realistic.
Even if their report is taken seriously, they note any change will take time. They also do not expect the industry to be able to effect change without help. The TEG wants government and regulator involvement if the long-term prospects of a crucial industry are to be ensured.
The key is to create an environment that nurtures innovation and here telcos could work collectively to make that happen.
“No telco has it all, but individual ones have strengths,” says Clarke. “If you could somehow combine the strengths of the particular telcos and create such an environment, things will emerge.”
The trick is diversity – get people from different domains together to make judgements as to what promising innovation looks like.
“Bring together the best people and marvelous things happen when you give them a few beers and tell them to solve a problem impacting all of them,” says Clarke. “How can we make that happen?”
Telecoms' innovation problem and its wider cost
Imagine how useful 3D video calls would have been this last year.
The technologies needed – a light field display and digital compression techniques to send the vast data generated across a network – do exist but practical holographic systems for communication remain years off.
But this is just the sort of application that telcos should be pursuing to benefit their businesses.
A call for innovation
“Innovation in our industry has always been problematic,” says Don Clarke, formerly of BT and CableLabs and co-author of a recent position paper outlining why telecoms needs to be more innovative.
Entitled Accelerating Innovation in the Telecommunications Arena, the paper’s co-authors include representatives from communications service providers (CSPs), Telefonica and Deutsche Telekom.
In an era of accelerating and disruptive change, CSPs are proving to be an impediment, argues the paper.
The CSPs’ networking infrastructure has its own inertia; the networks are complex, vast in scale and costly. The operators also require a solid business case before undertaking expensive network upgrades.
Such inertia is costly, not only for the CSPs but for the many industries that depend on connectivity.
But if the telecom operators are to boost innovation, practices must change. This is what the position paper looks to tackle.
NFV White Paper
Clarke was one of the authors of the original Network Functions Virtualisation (NFV) White Paper, published by ETSI in 2012.
The paper set out a blueprint as to how the telecom industry could adopt IT practices and move away from specialist telecom platforms running custom software. Such proprietary platforms made the CSPs beholden to systems vendors when it came to service upgrades.
The NFV paper also highlighted a need to attract new innovative players to telecoms.
“I see that paper as a catalyst,” says Clarke. “The ripple effect it has had has been enormous; everywhere you look, you see its influence.”
Clarke cites how the Linux Foundation has re-engineered its open-source activities around networking while Amazon Web Services now offers a cloud-native 5G core. Certain application programming interfaces (APIs) cited by Amazon as part of its 5G core originated in the NFV paper, says Clarke.
Software-based networking would have happened without the ETSI NFV white paper, stresses Clarke, but its backing by leading CSPs spurred the industry.
However, building a software-based network is hard, as the subsequent experiences of the CSPs have shown.
“You need to be a master of cloud technology, and telcos are not,” says Clarke. “But guess what? Riding to the rescue are the cloud operators; they are going to do what the telcos set out to do.”
For example, as well as hosting a 5G core, AWS is active at the network edge including its Internet of Things (IoT) Greengrass service. Microsoft, having acquired telecom vendors Metaswitch and Affirmed Networks, has launched ‘Azure for Operators’ to offer 5G, cloud and edge services. Meanwhile, Google has signed agreements with several leading CSPs to advance 5G mobile edge computing services.
“They [the hyperscalers] are creating the infrastructure within a cloud environment that will be carrier-grade and cloud-native, and they are competitive,” says Clarke.
The new ecosystem
The position paper describes the telecommunications ecosystem in three layers (see diagram).
The CSPs are examples of the physical infrastructure providers (bottom layer) that have fixed and wireless infrastructure providing connectivity. The physical infrastructure layer is where the telcos have their value – their ‘centre of gravity’ – and this won’t change, says Clarke.
The infrastructure layer also includes the access network which is the CSPs’ crown jewels.
“The telcos will always defend and upgrade that asset,” says Clarke, adding that the CSPs have never cut access R&D budgets. Access is the part of the network that accounts for the bulk of their spending. “Innovation in access is happening all the time but it is never fast enough.”
The middle, digital network layer is where the nodes responsible for switching and routing reside, as do the NFV and software-defined networking (SDN) functions. It is here where innovation is needed most.
Clarke points out that the middle and upper layers are blurring; they are shown separately in the diagram for historical reasons since the CSPs own the big switching centres and the fibre that connect them.
But the hyperscalers – with their data centres, fibre backbones, and NFV and SDN expertise – play in the middle layer too even if they are predominantly known as digital service providers, the uppermost layer.
The position paper’s goal is to address how CSPs can better address the upper two network layers while also attracting smaller players and start-ups to fuel innovation across all three.
Paper proposal
The paper identifies several key issues that curtail innovation in telecoms.
One is the difficulty for start-ups and small companies to play a role in telecoms and build a business.
Just how difficult it can be is highlighted by the closure of SDN-controller specialist, Lumina Networks, which was already engaged with two leading CSPs.
In a Telecom TV panel discussion about innovation in telecoms, that accompanied the paper’s publication, Andrew Coward, the then CEO of Lumina Networks, pointed out how start-ups require not just financial backing but assistance from the CSPs due to their limited resources compared to the established systems vendors.
It is hard for a start-up to respond to an operator’s request-for-proposals that can be thousands of pages long. And when they do, will the CSPs’ procurement departments consider them due to their size?
Coward argues that a portion of the CSP’ capital expenditure should be committed to start-ups. That, in turn, would instill greater venture capital confidence in telecoms.
The CSPs also have ‘organisational inertia’ in contrast to the hyperscalers, says Clarke.
“Big companies tend towards monocultures and that works very well if you are not doing anything from one year to the next,” he says.
The hyperscalers’ edge is their intellectual capital and they work continually to produce new capabilities. “They consume innovative brains far faster and with more reward than telcos do, and have the inverse mindset of the telcos,” says Clarke.
The goals of the innovation initiative are to get CSPs and the hyperscalers – the key digital service providers – to work more closely.
“The digital service providers need to articulate the importance of telecoms to their future business model instead of working around it,” says Clarke.
Clarke hopes the digital service providers will step up and help the telecom industry be more dynamic given the future of their businesses depend on the infrastructure improving.
In turn, the CSPs need to stand up and articulate their value. This will attract investors and encourage start-ups to become engaged. It will also force the telcos to be more innovative and overcome some of the procurement barriers, he says.
Ultimately, new types of collaboration need to emerge that will address the issue of innovation.
Next steps
Work has advanced since the paper was published in June and additional players have joined the initiative, to be detailed soon.
“This is the beginning of what we hope will be a much more interesting dialogue, because of the diversity of players we have in the room,” says Clarke. “It is time to wake up, not only because of the need for innovation in our industry but because we are an innovation retardant everywhere else.”
Further information:
Telecom TV’s panel discussion: Part 2, click here
Tom Nolle’s response to the Accelerating Innovation in the Telecommunications Arena paper, click here
What the cable operators are planning for NFV and SDN
Cable operators are working on adding wireless to their fixed access networks using NFV and SDN technologies.
Don Clarke“Cable operators are now every bit as informed about NFV and SDN as the telcos are, but they are not out there talking too much about it,” says Don Clarke, principal architect for network technologies at CableLabs, the R&D organisation serving the cable operators.
Clarke is well placed to comment. While at BT, he initiated the industry collaboration on NFV and edited the original white paper which introduced the NFV concept and outlined the operators’ vision for NFV.
NFV plans
The cable operators are planning developments by exploiting the Central Office Re-architected as a Datacenter (CORD) initiative being pursued by the wider telecom community. Comcast is one cable operator that has already joined the Open Networking Lab’s (ON.Lab) CORD initiative. The aim is to add a data centre capability to the cable operators’ access network onto which wireless will be added.
CableLabs is investigating adding high-bandwidth wireless to the cable network using small cells, and the role 5G will play. The cable operators use DOCSIS as their broadband access network technology and it is ideally suited for small cells once these become mainstream, says Clarke: “How you overlay wireless on top of that network is probably where there is going to be some significant opportunities in the next few years.”
One project CableLabs is working on is helping cable operators provision services more efficiently. At present, operators deliver services over several networks: DOCSIS, EPON and in some cases, wireless. CableLabs has been working for a couple of years on simplifying the provisioning process so that the system is agnostic to the underlying networks. “The easiest way to do that is to abstract and virtualize the lower-level functionality; we call that virtual provisioning,” says Clarke.
CableLabs recently published its Virtual Provisioning Interfaces Technical Report on this topic and is developing data models and information models for the various access technologies so that they can be abstracted. The result will be more efficient provisioning of services irrespective of the underlying access technology, says Clarke.
How you overlay wireless on top of that network is probably where there is going to be some significant opportunities in the next few years
SNAPS
CableLabs is also looking at how to virtualise functionality cable operators may deploy near the edge of their networks.
“As the cable network evolves to do different things and adds more capabilities, CableLabs is looking at the technology platform that would do that,” says Clarke.
To this aim, CableLabs has created the SDN-NFV Application development Platform and Stack - SNAPS - which it has contributed to the Open Platform for NFV (OPNFV) group, part of the open source management organisation, The Linux Foundation.
SNAPS is a reference platform to be located near the network edge, and possibly at the cable head-end where cable operators deliver video over their networks. The reference platform makes use of the cloud-based operating system, OpenStack, and other open source components such as OpenDaylight, and is being used to instantiate virtual network functions (VNFs) in a real-time dynamic way. “The classic NFV vision,” says Clarke.
CableLabs' Randy Levensalor says one challenge facing cable operators is that, like telcos, they have separate cloud infrastructures for their services and that impacts their bottom line.
Cable operators are now every bit as informed about NFV and SDN as the telcos are, but they are not out there talking too much about it
“You have one [cloud infrastructure] for business services, one for video delivery and one for IT, and you are operationally less efficient when you have those different stacks,” says Levensalor, lead software architect at CableLabs. “With SNAPS, you bring together all the capabilities that are needed in a reference configuration that can be replicated.”
This platform can support local compute with low latency. "We are not able to say much but there is a longer-term vision for that capability that we’ll develop new applications around,” says Clarke.
Challenges and opportunities
The challenges facing cable operators concerning NFV and SDN are the same as those facing the telcos, such as how to orchestrate and manage virtual networks and do it in a way that avoids vendor lock-in.
“The whole industry wants an open ecosystem where we can buy virtual network functions from one vendor and connect them to virtual network functions and other components from different vendors to create an end-to-end platform with the best capabilities at any given time,” says Clarke.
He also believes that cable operators can move more quickly than telcos because of how they collaborate via CableLabs, their research hub. However, the cable operators' progress is inevitably linked to that of the telcos given they want to use the same SDN and NFV technologies to achieve economies of scale. “So we can’t diverge in the areas that need to be common, but we can move more quickly in areas where the cable network has an inherent advantage, for example in the access network,” says Clarke.
Telcos eye servers & software to meet networking needs
- The Network Functions Virtualisation (NFV) initiative aims to use common servers for networking functions
- The initiative promises to be industry disruptive
"The sheer massive [server] volumes is generating an innovation dynamic that is far beyond what we would expect to see in networking"
Don Clarke, NFV
Telcos want to embrace the rapid developments in IT to benefit their networks and operations.
The Network Functions Virtualisation (NFV) initiative, set up by the European Telecommunications Standards Institute (ETSI), has started work to use servers and virtualisation technology to replace the many specialist hardware boxes in their networks. Such boxes can be expensive to maintain, consume valuable floor space and power, and add to the operators' already complex operations support systems (OSS).
"Data centre technology has evolved to the point where the raw throughput of the compute resources is sufficient to do things in networking that previously could only be done with bespoke hardware and software," says Don Clarke, technical manager of the NFV industry specification group, and who is BT's head of network evolution innovation. "The data centre is commoditising server hardware, and enormous amounts of software innovation - in applications and operations - is being applied.”
"Everything above Layer 2 is in the compute domain and can be put on industry-standard servers"
The operators have been exploring independently how IT technology can be applied to networking. Now they have joined forces via the NFV initiative.
"The most exciting thing about the technology is piggybacking on the innovation that is going on in the data centre," says Clarke. "The sheer massive volumes is generating an innovation dynamic that is far beyond what we would expect to see in networking."
Another key advantage is that once networks become software-based, enormous amounts of flexibility results when creating new services, bringing them to market quickly while also reducing costs.
NFV and SDN
The NFV initiative is being promoted as a complement to software-defined networking (SDN).
The complementary relationship between NFV and SDN. Source: NFV.
SDN is focussed on control mechanisms to reconfigure networks that separate the control plane and the data plane. The transport network can be seen as dumb pipes with the control mechanisms adding the intelligence.
“There are other areas of the network where there is intrinsic complexity of processing rather than raw throughput,” says Clarke.
These include firewalls, session border controllers, deep packet inspection boxes and gateways - all functions that can be ported onto servers. Indeed, once running as software on servers such networking functions can be virtualised.
"Everything above Layer 2 is in the compute domain and can be put on industry-standard servers,” says Clarke. This could even include core IP routers but clearly that is not the best use of general-purpose computing, and the initial focus will be equipment at the edge of the network.
Clarke describes how operators will virtualise network elements and interface them to their existing OSS systems. “We see SDN as a longer journey for us,” he says. “In the meantime we want to get the benefits of network virtualisation alongside existing networks and reusing our OSS where we can.”
NFV will first be applied to appliances that lend themselves to virtualisation and where the impact on the OSS will be minimal. Here the appliance will be loaded as software on a common server instead of current bespoke systems situated at the network's end points. “You [as an operator] can start to draw a list of target things as to what will be of most interest,” says Clarke.
Virtualised network appliances are not a new concept and examples are already available on the market. Vanu's software-based radio access network technology is one such example. “What has changed is the compute resources available in servers is now sufficient, and the volume of servers [made] is so massive compared to five years ago,” says Clarke
The NFV forum aims to create an industry-wide understanding as to what the challenges are while ensuring that there are common tools for operators that will also increase the total available market.
Clarke stresses that the physical shape of operators' networks - such as local exchange numbers - will not change greatly with the uptake of NFV. “But the kind of equipment in those locations will change, and that equipment will be server-based," says Clarke.
"One of the things the software world has shown us is that if you sit on your hands, a player comes out of nowhere and takes your business"
One issue for operators is their telecom-specific requirements. Equipment is typically hardened and has strict reliability requirements. In turn, operators' central offices are not as well air conditioned as data centres. This may require innovation around reliability and resilience in software such that should a server fail, the system adapts and the server workload is moved elsewhere. The faulty server can then be replaced by an engineer on a scheduled service visit rather than an emergency one.
"Once you get into the software world, all kinds of interesting things that enhance resilience and reliability become possible," says Clarke.
Industry disruption
The NFV initiative could prove disruptive for many telecom vendors.
"This is potentially massively disruptive," says Clarke. "But what is so positive about this is that it is new." Moreover, this is a development that operators are flagging to vendors as something that they want.
Clarke admits that many vendors have existing product lines that they will want to protect. But these vendors have unique telecom networking expertise which no IT start-up entering the field can match.
"It is all about timing," says Clarke. "When do they [telecom vendors] decisively move their product portfolio to a software version is an internal battle that is happening right now. Yes, it is disruptive, but only if they sit on their hands and do nothing and their competitors move first."
Clarke is optimistic about to the vendors' response to the initiative. "One of the things the software world has shown us is that if you sit on your hands, a player comes out of nowhere and takes your business," he says.
Once operators deploy software-based network elements, they will be able to do new things with regard services. "Different kinds of service profiles, different kinds of capabilities and different billing arrangements become possible because it is software- not hardware-based."
Work status
The NFV initiative was unveiled late last year with the first meeting being held in January. The initiative includes operators such as AT&T, BT, Deutsche Telekom, Orange, Telecom Italia, Telefonica and Verizon as well as telecoms equipment vendors, IT vendors and technology providers.
One of the meeting's first tasks was to identify the issues to be addressed to enable the use of servers for telecom functions. Around 60 companies attended the meeting - including 20-odd operators - to create the organisational structure to address these issues.
Two experts groups - on security, and on performance and portability - were set up. “We see these issues as key for the four working groups,” says Clarke. These four working groups cover software architecture, infrastructure, reliability and resilience, and orchestration and management.
Work has started on the requirement specifications, with calls between the members taking place each day, says Clarke. The NFV work is expected to be completed by the end of 2014.
Further information:
White Paper: Network Functions Virtualisation: An Introduction, Benefits, Enablers, Challenges & Call for Action, click here