As I look back over the last few years of my career, I have witnessed an incredible evolution of cloud services and one common denominator that I have seen is how important a role SDN and SD-WAN have played. As enterprises have adopted cloud-based architectures to drive the efficiency and scale of business applications, network automation through SDN and then SD-WAN has been an enabling technology every step of the way. The following diagram depicts some of the milestones in this evolution.
This really started with the advent of virtualised private data centres. Prior to this trend, enterprise applications were delivered from dedicated servers & appliances with rigid network segregation via VLANs and DMZs. There was no network automation or agility to speak of. I remember working on SDN technology at this time to deliver secure and automated connectivity (e.g. virtual networking) in the private cloud or private data center across diverse virtual workloads. Nuage Networks’ original SDN solution was specifically designed to be extensible outside of the boundaries of the private data center and this design approach proved to be prophetic.
While SDN emerged in the DC, SD-WAN followed to provide the same type of network automation but instead of connecting workloads within a data center, it was initially designed to connect branches across a WAN and it started to generate a lot of hype in the market. SD-WAN intended to securely connect enterprise branch sites to each other over any transport (Internet, MPLS or LTE), with a cloud-based management/control plane enabling agile network programming while providing application level insight. At this time, Nuage Networks leveraged the same platform that was developed for SDN (i.e. Virtualized Services Platform (VSP)) to provide these nascent SD-WAN services.
As SD-WAN gained traction, public cloud services like Infrastructure as-a-Service (IaaS) and Platform as-a-Service (PaaS) started to gain mass market adoption as enterprises wanted to trade CAPEX for OPEX and started to host their business applications ‘in the cloud.’ These services offered flexibility and scalability, and many enterprises deployed hybrid clouds where both private and public cloud hosting options were used. The emergence of multi-cloud deployments followed where multiple public cloud services from different vendors were used to host the same application to enhance resiliency while avoiding vendor lock-in.
SD-WAN was needed to support this next phase in cloud evolution and several SD-WAN solutions adapted to cater to the needs of the adoption of public cloud services. They did this by deploying their SD-WAN management/control stacks through virtual gateways in the cloud, allowing these public services to be modeled just like another branch office. Nuage Networks was one of the leaders in this space by integrating the virtualized version of the Network Services Gateway (NSG-v) in the AWS and Azure clouds to name a couple of examples. This approach not only created further synergy between SD-WAN and public clouds, but it also allowed for public cloud connectivity to be automated with full fidelity of network policy and insight into public cloud applications. Furthermore, SD-WAN could now optimise the network based on public cloud application performance.
Software as a Service (SaaS) applications (Office 365, Salesforce or GitHub, etc.) was another form of cloud consumption prevalent across enterprises, irrespective of size or geography. SD-WAN ensured a seamless application performance for this type of cloud access by optimising network resources. SD-WAN was also used complement SaaS consumption by routing certain application packet flows to cloud-hosted security stacks, like Zscaler, to sanitize SaaS traffic.
However, this shift in cloud services and cloud-based architectures created security concerns that needed to be addressed. As enterprise network boundaries were being expanded into the cloud and traffic was no longer delivered through a centralized private and secure data center hub, security concerns started to emerge. The attack surface increased dramatically, with “east-west” traffic being the source of most attack vectors. In order to deal with this scenario, SD-WAN needed to reinvent itself beyond the first generation of “connectivity-centric” solutions. A next generation SD-WAN platform was needed to provide deep insight into east to west traffic, with micro-segmentation all the way from users in branch offices to applications in the cloud, with automated responses to security events. It was also essential for the next generation SD-WAN platform to extend its policy reach all the way to application end points in the cloud and not be restricted to the cloud periphery.
In today’s cloud landscape, public cloud services are aggressively shifting to the edge of the network as 5G technologies combined with IoT SLA requirements are pushing the limits of performance that centralized cloud services can offer. These edge clouds move the cloud boundary closer to the enterprise to serve high bandwidth, latency sensitive applications. Specifically, one type of edge cloud is formed by extending cloud infrastructures to the edge of the network, in a service provider’s facility, close to a 5G radio tower. This service is geared toward very low latency and high bandwidth applications. An example here is AWS Wavelength. The other implementation we are seeing is public cloud infrastructures being deployed ‘on-premise’ for ultra low latency applications where often actionable analytics are also performed locally. These services are geared toward manufacturing and robotics where immediate feedback is needed.
With the distributed nature of edge clouds and corresponding services, the role of SD-WAN’s end-to-end visibility and control is now more important than ever to program the network to ensure that each application receives the service and performance it needs. The edge cloud services require secure, seamless connectivity to cloud components, as well as providing network SLAs that SD-WAN should measure and assure.
Over the last few years I have witnessed an incredible journey of digital transformation as enterprises have embraced virtualization and the cloud. During this journey, SD-WAN capabilities have evolved to enable this transformation. Nuage Networks has been at the forefront of this technological shift. Today, technology may be evolving even more quickly to accommodate the next generation of IT services unlocked by communication technologies like 5G. Nuage Networks and its SDN and SD-WAN technologies will be essential to ensure that these services can be consumed with agility while eliminating any network restrictions.