When I look back over the past few years of my career, I've seen an incredible evolution in cloud services. A common denominator that I've seen is how important SDN and SD-WAN played. With companies adopting cloud-based architectures to increase the efficiency and scale of business applications, network automation over SDN and then over SD-WAN has been an important technology every step of the way. The following diagram shows some of the milestones in this development.
It really started with the advent of virtualized private data centers. Against this trend, enterprise applications were provided by dedicated servers and appliances with rigid network separation via VLANs and DMZs. There was no significant network automation or agility. I remember working on SDN technology at that point to provide secure and automated connectivity (e.g. virtual networks) in the private cloud or data center for various virtual workloads. Nuage Networks' original SDN solution was specifically designed to be expandable beyond the confines of the private data center, and this design approach proved prophetic.
While SDN appeared 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 originally designed to connect branches across a WAN, and lots of hype started in the market. SD-WAN should securely connect company locations with each other via any transport (Internet, MPLS or LTE). A cloud-based administration / control level enables agile network programming and offers insights at the application level. At the time, Nuage Networks was using the same platform developed for SDN (i.e., Virtualized Services Platform (VSP)) to provide these emerging SD-WAN services.
With the proliferation of SD-WAN, public cloud services such as Infrastructure as a Service (IaaS) and Platform as a Service (PaaS) became increasingly popular as companies wanted to trade CAPEX for OPEX and host their business applications "in the cloud". These services offered flexibility and scalability, and many companies use hybrid clouds that use both private and public cloud hosting options. Multi-cloud deployments followed, using multiple public cloud services from different vendors to host the same application to improve resilience while avoiding vendor loyalty.
SD-WAN was needed to support this next phase of cloud development and several SD-WAN solutions that were adapted to the requirements of the introduction of public cloud services. To do this, they provided their SD-WAN management / control stacks via virtual gateways in the cloud, so that these public services can be modeled like any other branch. Nuage Networks has been a leader in this area by integrating the virtualized version of the Network Services Gateway (NSG-v) into the AWS and Azure clouds, to name just a few. This approach not only led to further synergies between SD-WAN and public clouds, but also enabled the automation of public cloud connectivity with full compliance with network guidelines and insight into public cloud applications. In addition, SD-WAN has now been able to optimize the network based on the performance of public cloud applications.
SaaS (Software as a Service) applications (Office 365, Salesforce, or GitHub, etc.) were another form of cloud consumption that was common in companies regardless of size or region. By optimizing network resources, SD-WAN ensured seamless application performance for this type of cloud access. SD-WAN was also used to augment SaaS consumption by forwarding certain application packet flows to cloud-hosted security stacks such as Zscaler to clean up SaaS traffic.
However, this shift in cloud services and cloud-based architectures led to security concerns that needed to be addressed. When the company's network boundaries were extended to the cloud and data traffic was no longer provided via a central, private and secure data center hub, security concerns arose. The attack surface increased dramatically, with "east-west" traffic being the source of most attack vectors. To cope with this scenario, SD-WAN had to reinvent itself beyond the first generation of "connectivity-oriented" solutions. A next-generation SD-WAN platform was needed to get a deep insight into east-west traffic. Micro-segmentation ranges from branch office users to applications in the cloud and provides automated responses to security events. For the next generation SD-WAN platform, it was also important to extend their policy reach to application endpoints in the cloud rather than being limited to the cloud peripherals.
In today's cloud landscape, public cloud services are aggressively moving to the edge of the network as 5G technologies combined with IoT SLA requirements extend the performance limits of centralized cloud services. These edge clouds move the cloud boundary closer to the enterprise to deliver high bandwidth, latency sensitive applications. In particular, a kind of edge cloud is formed by expanding cloud infrastructures to the edge of the network in the establishment of a service provider near a 5G radio tower. This service is aimed at applications with very low latency and high bandwidth. An example of this is AWS Wavelength. The other implementation we see is public cloud infrastructures that are provided “on-premise” for extremely low-latency applications, which often do locally-deployable analytics. These services are focused on manufacturing and robotics, where immediate feedback is required.
Given the distributed nature of edge clouds and related services, the role of end-to-end visibility and control of SD-WAN is more important today than ever to program the network so that each application receives the service and performance, that she needs. Edge cloud services require secure, seamless connectivity to cloud components, as well as the provision of network SLAs that SD-WAN should measure and ensure.
In the past few years, I've had an incredible journey of digital transformation as companies introduced virtualization and the cloud. During this trip, SD-WAN functions were developed to enable this transformation. Nuage Networks was at the forefront of this technological change. Today, technology may evolve even faster to meet the next generation of IT services that are unlocked through communication technologies like 5G. Nuage Networks and its SDN and SD-WAN technologies are essential to ensure that these services can be used flexibly without the need for network restrictions.