16 December 2016

offers a radical way to design, deploy and manage a multi-site WAN. It says configuration of the service is provided by netadmins in a business environment, rather than an engineer in a carrier environment.

t’s no secret that most enterprise IT managers and CIOs hate their wide area networks, according to Joachim Sinzig, VP of portfolio management at Colt Technology Services. “The WAN is typically an expensive, administrative nightmare, with lead times for bandwidth running into months. Putting it simply, the customer wants secure, guaranteed delivery with quality of service for their data network. But they don’t want increasing data capacity requirements to mean more expensive bandwidth circuits.”

Danny Phillips, Citrix Systems’ EMEA director of NetScaler product marketing, agrees. He says traditional WAN options have been based around expensive MPLS offerings from operators, and typically have long delivery times as well as multi-year contracts associated with them. “With bandwidth demands continuing to increase year-over-year, organisations see traditional WAN services as putting increasing pressures on the IT budget.”

The proponents of SD-WAN believe it offers huge potential to lower costs by managing how applications use different WAN services, thereby limiting the need for MPLS circuits for all applications. For instance, Sinzig says enterprises can use the public internet for services that are not latency critical (such as email or web browsing), while reserving the data network for high-bandwidth applications that are mission critical.

According to Silver Peak, as adoption of cloud applications and services continues to grow, the SD-WAN market is emerging as an economical and effective way to connect users to applications and for enterprises to operate at ‘cloud speed’. Citing predictions made by Gartner, the company’s EMEA VP Nick Applegarth says that over the next two years SaaS will become the dominant model for consuming application functionality for around 80 per cent of all organisations. “To keep up with this pace, businesses need to re-evaluate their WAN requirements, and SD-WAN is now a viable option to overcome challenges such as improving responsiveness and agility of the business and network, as well as reducing costs and providing better performance for cloud applications.”

Clearly then, SD-WAN is not just all about saving money. Milton Keynes-based Comms365 is a B2B mobile data and fixed line communications provider. It believes the ever-growing consumption of cloud computing and SaaS is putting “significant pressure” on traditional WAN architecture which is struggling to deliver application performance to users over legacy router hardware, complex network systems, and increasingly congested access ‘pipes’. 

Like many of his peers, Nick Sacke, Comms365’s head of product and IoT, agrees that existing WAN solutions based on MPLS technology are expensive, adding that they don’t easily allow the use of ‘commodity broadband’ access connections to help lower the overall network costs. “The prospect of replacing CPE branch routers with software has driven many networking vendors to launch SD-WAN offerings. Carriers/managed service providers are also now launching managed SD-WAN services as an alternative to the original managed routers installed five years or more ago.”

Sacke also quotes Gartner which has reported that the effects of rapid adoption of SD-WAN by enterprises globally is making it all but impossible for incumbent equipment and service providers to maintain their revenues, margins and market shares. “As a result, industry giants such as Cisco, Citrix, HP, BT and others have formally committed to the SDN and NFV business models to ‘re-invent’ their networking businesses as software, opening up new revenue streams. The investment by these technology giants (in particular the carriers who are responsible for the bulk of WAN technology solution decision-making) and growing customer appetite for the solution benefits, makes SD-WAN an extremely attractive, fast-growing networking technology solution.”

SDN has been around for several years now but still remains a hot industry topic. And in the words of Paul Hennin, international marketing director with enterprise mobility specialist Aerohive Networks, it is driving the future of networking by “shifting the mindset around planning, implementing, managing and using networks”. But he points out that SDN can be seen as less of a network-wide technology and more of a data centre solution. “As a result, while SDN is a starting point, it’s not the definitive protocol so cannot alone shape which direction networking is heading. This is where SD-WAN can help.”

Defining the software defined WAN

So what exactly does a software defined wide area network entail? As Hennin explains, the SD-WAN separates the control and data planes of the WAN, and enables a degree of control across multiple WAN elements, both physical and virtual, that were otherwise not possible. “Importantly, a portion of the WAN community recognises the need to software-define the WAN in a manner not necessarily identical to the protocols that today define SDN – so they’re related but different due to essentially different requirements.”

He goes on to say that there’s something else that businesses also need to take into account: SD-LAN. “This is extending software-defined techniques into the access layer of switches, APs, and perhaps even eventually into client devices (via drivers). Crucially, success in SD-LAN ultimately depends to a very large degree on the architecture of a given WLAN system solution.”

Hennin says architecture has traditionally been thought of as benefiting the overall performance characteristics of a given installation. But now it’s contributing to advances in capacity, reliability, operations productivity, security, scalability, total cost of ownership and much more. “With the next frontier based on a wireless-first approach, the WLAN industry is set to continue evolving, and businesses need to take advantage of this.”

Others may not entirely agree with this approach. For instance, Citrix’s Phillips says many vendors focus on different elements of SD-WAN, with these elements typically representing the “DNA” of their products. He accuses vendors of “creating confusion” in the hopes of reinforcing their own offerings, and this presents a challenge that many organisations will face when looking at SD-WAN.

Citrix says SD-WAN is about combining a collection of branch edge functions – routing, path selection, WAN optimisation, firewall and web gateways – into a single appliance with a common management tool. “This is not vCPE loaded with different vendor’s virtual appliances, as this merely puts the challenge of management back on the organisation,” says Phillips. “SD-WAN solutions offer network functions that are orchestrated by a simple-to-use management application. These network functions must provide reliable, secure and effective application delivery, and the management tool greater simplifies the cost of network administration.”

All this seems to illustrate a point made by Paul Griffiths, senior director of Riverbed’s Advanced Technology Group, who says all vendors will have their own definition of what SD-WAN is. But he adds all of them should realise that it offers three distinct benefits. As well as the cost-savings capabilities that have already been discussed, Griffiths says SD-WAN permits an increased level of availability, and also provides a greater degree of flexibility and agility. 

“SD-WAN offers the ability to deploy equipment with a ‘zero-touch provisioning’ methodology, make on-the-fly adjustments to a network’s performance and application delivery, and meet a business’ ever-changing needs. 

“It also enables organisations to direct traffic and deploy network services across a WAN from a centralised location. Ultimately, this translates into reduced costs and operational complexity, and increased optimisation to deliver superior-performing apps and experiences to users.”

Migrating to a network

Riverbed points out that there’s work to be done before the migration to SD-WAN even starts. According to Griffiths, network managers need to begin by taking a “top down” approach to see how their business applications are performing. Using visibility tools within the ecosystem environment will give them a holistic view of the IT infrastructure and enable them to determine how users interact with the applications in real time. 

“This allows the manager to see the ‘bigger picture’ before the business looks to migrate to an SD-WAN environment,” says Griffiths. “Without this insight, enterprises will have no indication of the expectations or what the benefits will be when you move to SD-WAN.”

If there is one thing that all vendors agree on when it comes to SD-WAN, it is the clear need for centralised management. It is this that will enable network managers to carry out their jobs with the ‘zero-touch provisioning’ alluded to above. For instance, Comms365’s Sacke adds his support when he says: “SD-WAN services should offer a management console/portal where network managers can set up and manage their sites. The console should allow visualisation and control of the current site connectivity status, configuration, routing policies, alerting and security settings.”

Colt proved this earlier this year when it announced that it had expanded its managed SD-WAN service to multiple countries across Europe (see News, Oct 2016). Sinzig says: “Colt claims both agility and economic advantage in the delivery of NFV-based services for the WAN and branch office by accelerating time-to-service while reducing total cost of ownership due to centralised management for all sites.”

That “agility” he refers to is made possible thanks to an NFV-based platform that integrates on-demand elasticity and multi-tenancy, and combines SD-WAN software with open and scalable general purpose server hardware at the customer’s premises.

So what other tools, hardware, software and services should network managers look for when migrating to an SD-WAN? Silver Peak says once a decision to employ either a physical or virtual appliance has been made, network managers should also ensure that WAN virtual overlays offer encrypted tunnels and provide high levels of performance, security and segmentation edge-to-edge.

“Path conditioning technologies will also ensure that packet loss, latency, jitter and throughput is monitored and managed within SLA thresholds,” advises Applegarth. “This is important, especially when using internet connections and even MPLS, because path conditioning can reconstruct packets lost in transit without incurring the overhead or latency of retransmitting them.

“Finally, SD-WAN solutions should seamlessly integrate WAN optimisation to further accelerate applications and reduce the amount of data passing across the WAN.”

So what about existing and legacy IT assets – where do they fit in? Griffiths says it is important to realise that an SD-WAN environment is not a ‘rip and replace’ technology framework. “Ideally, it should provide a way for customers to move away from legacy deployment and management of IT, as 20th century approaches and technology systems are simply unable to scale and move with 21st century business needs. It does not have to be instantaneous though as this could cause widespread disruption for some organisations.”

Riverbed claims its SteelConnect platform provides organisations with the SD-WAN tools and products needed to be able to fully migrate towards an SD-WAN environment. It also ensures that technology is able to interact with legacy routing infrastructures and security mechanisms in such a way that allows
a phased approach to deployment. 

Furthermore, the firm adds that organisations can control their design and deployment in a way that allows them to build out the complete SD-WAN infrastructure within the management system of SteelConnect without installing a single device. “Then, when the time is right, they can deploy SD-WAN capable components on a case by case basis,” says Griffiths.

Silver Peak also points out that moving to an SD-WAN should not be an all or nothing approach. “One of the biggest concerns with SD-WAN technology is the extensibility with traditional WAN architecture,” says Applegarth. “Some SD-WAN vendors require existing traditional WAN equipment to be replaced when migrating to their products, resulting in disruption to the WAN and interruption to applications during the transition. However, there are SD-WAN solutions available today that are extensible with existing WAN infrastructure and interoperate within an existing WAN, providing a seamless migration.

“Indeed, companies can begin their journey to an SD-WAN by deploying a hybrid WAN which allows them to move at their own pace. With a hybrid WAN, businesses can deploy lower-cost broadband internet services as an alternative to connecting to cloud applications when MPLS contracts come up for renewal. This creates the opportunity to downsize MPLS bandwidth and migrate additional services slowly to the cloud, as desired.”

Colt supports this type of approach. Typically, for customer sites that are ‘on-net’ (i.e. directly connected with Colt fibre), Sinzig says bandwidth scales in a very cost-efficient way but adds that this has not been the case with off-net sites. 

“The introduction of SD-WAN removes these limitations by enabling a path to the public internet for those apps which are not latency-critical. Customers can then reserve off-net data capacity for more business-critical applications. The end result is that a hybrid network is formed where non-critical data is offloaded to a secured internet tunnel, freeing-up MPLS bandwidth for business critical data, efficiently increasing the total bandwidth to branch sites. Data over the internet is secured by using IPSec tunnels, and the customer is free to use their existing ISP if they so wish.”

The role of the network manager

SD-WAN promises to not only reduce the cost of running a wide area network but also simplify its management. So where does all that leave the network manager?

“Businesses are adding more commodity internet into the traditional WAN mix to better balance network performance and price,” says Sinzig. “The result is increased overheads in terms of network management, configuration and orchestration – until now. SD-WAN reduces the level of expertise required to configure the branch to what Gartner claims is the equivalent of setting up a basic home wireless network with consumer-grade equipment.” 

Sinzig says Colt’s intelligent SD-WAN platform enables customers to dynamically route traffic to manage both secure and internet data in real time. This can be configured by Colt or the customer. “So the network manager can in fact take on as much or as little of the management as they desire, potentially giving them more time and resource back.”

Silver Peak agrees that SD-WAN technology makes the role of the IT or network manager inherently simpler. Applegarth says: “This is not least because SD-WANs are managed or ‘orchestrated’ centrally. While operational training is required, it is only necessary for IT staff based at a company’s headquarters, as branch locations no longer require specialised networking expertise.”

As an example, he says configuration changes can be handled centrally with IT programming, and all it takes is a single command to ‘push’ this to all of the SD-WAN appliances. Similarly, zero-touch provisioning capabilities mean new site setups can be handled centrally with no localised expertise needed. Furthermore, policy management can be handled centrally in alignment with business aims.

“Once an SD-WAN is up and running, many of the day-to-day tasks can be automated and monitored via a centralised management system,” says Applegarth. “This enables IT staff and resources to be directed toward initiatives that will advance business objectives including revenue growth, improved productivity and ultimately higher profitability.”

Comms365 describes SD-WAN as a “radical” new way to design, deploy and manage a multi-site WAN. As a result, Sacke says the IT manager can now play an active role in the programming and ongoing administration of the WAN, no longer having to rely on carrier engineering helpdesks to make required adds, deletions or changes.

“Configuration of the service is provided by network administrators in a business environment, rather than an engineer in a carrier environment,” says Sacke. “Edge and core devices automatically and securely route traffic from the customer edge based on application and availability over multiple access links, which are carrier agnostic. Customer sites become ‘application aware’ to enhance the customer experience of the cloud.” 

SD-WAN can be a revolutionary concept for some IT teams to understand as it provides a completely different way of operating wide area infrastructure. But through education, Griffiths says they can move away from a mindset that previously encouraged configuration on a device-by-device level. 

“IT managers should steer away from a siloed mentality when it comes to discussing IT infrastructure. For example, [there should be] distinct conversations about the data centre and network, separated from the wider discussions centred on business goals. With SD-WAN, these should no longer be treated as mutually exclusive. All parties must work together to migrate to an SD-WAN environment successfully.” 

Griffiths believes that collaboration between IT teams results in an open approach to IT management. “Whether siloed or not, the IT team needs to be able to understand the language of business. One of the other skills the IT manager or network manager needs to hone is working towards a way of communication with the wider business in a way that both groups can talk a common language – SD-WAN enables this bilateral conversation.”

Real future or just hype?

Aerohive reckons that as an emerging architecture, SDN offers great possibilities in an era that will be defined by the demand for ever higher bandwidth. “SD-WAN and SD-LAN take this to the next level and will become increasingly essential in the coming years,” says Hennin. “Modern networks must continuously adjust and adapt to keep up with the pace of change that mobility has created. This is unachievable in traditional network architectures, which makes the move to SD-WAN and indeed SD-LAN inevitable for any organisation that wants to stay ahead of the competition.”

So does that mean SD-WAN represents the real future for enterprise networking? Not quite, according to Citrix’s Phillips: “SD-WAN is still quite new and loosely defined, and so it might be a step too far to say the move to SD-WAN is ‘inevitable’. However, organisations are constantly looking at new technologies that offer the ability to add reliability and security into their WANs, while also offering the promise of lowering the costs of application delivery.”

Riverbed reckons that a positive side effect of SD-WAN will see applications become more distributed again. This requires the WAN to evolve toward a hybrid mix that combines the performance of on premise hardware with the agility and elasticity of cloud based network functions. So does the firm consider SD-WAN to be the future?

“We’ve seen pendulum swings of various technologies from one extreme to another over the past several years,” says Griffiths. “There was the move from consolidated architectures to distributed architectures back to some sort of consolidation again, and this is perhaps where we are moving away from once more. Organisations saw the benefit of consolidating applications centrally, and now they can move those applications and push them to the public cloud as users are demanding access to applications virtually anywhere.”

For Silver Peak, the shift to SD-WAN is inescapable. Applegarth says this will be mainly driven by the accelerating migration of applications from the data centre to the cloud. 

“The adoption of virtualisation and the cloud across traditional WAN architectures, such as MPLS, are proving costly and ineffective in connecting users in branch offices directly to cloud-based applications. As cloud initiatives gain momentum and traction, companies are quickly embracing the favourable economics and relative simplicity of leveraging broadband connectivity to connect users to applications with the performance, security and reliability required to move forward.”

Other companies also see SD-WAN playing a key role in the future networks. For instance,  Comms365 forecasts that every multi-site network will at least evaluate, if not adopt, SD-WAN as a solution. And Colt points out that while the technology doesn’t act as a silver bullet for all an organisation’s WAN problems, it does address some of the biggest pain points.

VeloCloud claims first with new SD-WAN system that offers voice quality monitoring

With its Edge device, VeloCloud says users can deploy a cloud-delivered SD-WAN in two minutes.

VeloCloud Networks has launched what it says is the industry’s first SD-WAN solution to offer a fully featured voice-quality monitoring capability. 

VeloCloud VQM comprises a passive agent on the company’s Edge CPE. According to the US-based cloud SD-WAN specialist, it continuously monitors voice calls to proactively identify any performance issues on enterprise and service provider networks. This then enables them to monitor, diagnose and troubleshoot network issues before they can impact business-critical voice communications. 

VeloCloud has developed its new VoIP performance management software to support an extensive array of codec technologies. It adds that VQM provides listening and conversational call-quality metrics in both R-Factor and MOS (mean opinion score) formats. It is said to offer detailed diagnostic information, giving network managers both high-level metrics and the ability to drill down to identify specific problems.

VeloCloud claims to have more than 300 enterprise customers and service providers around the world. The company reckons VeloCloud VQM will deliver “significant” benefits to these users, including fast installation, continuous monitoring and pre-emptive identification, and resolution of network issues even before a customer becomes aware or is impacted by a problem. 

Furthermore, VeloCloud says its platform reduces the branch office footprint, and that it continues to build on the benefits of its cloud-delivered SD-WAN architecture by delivering support for on-premises or in the cloud voice services. “Integrated VQM with single click virtual service enablement eliminates multiple physical appliances in enterprise branch offices and expensive truck rolls,” says Steve Woo, vice president of products and co-founder at VeloCloud.