IT networking has changed dramatically over the past decade. For starters, many organizations have been able to divest themselves from on-premises network infrastructures and instead connect their most important applications and services to the public cloud. This switch has fueled tremendous growth for business cloud ecosystems such as Microsoft Azure and Amazon Web Services, which can provide networking resources on-demand.
Moreover, there has been the recent rise of software-defined networking as well as the more specific software-defined wide area network. According to IDC's 2016 projections, the SDN market will have a 53.9 percent compound annual growth rate from 2014 to 2020, ultimately reaching $12.5 billion in value. But what are SDN and SD-WAN, exactly? And what do these new families of technologies mean for Cisco certifications?
Understanding SDN and SD-WAN
Let's start with a few definitions:
- SDN is the decoupling of a network's control plane (where decisions are made about packets) from its data plane (where the packets are actually forwarded). The idea is to give network administrators more flexibility in how they control their networks, by freeing them from the need to touch individual switches. Instead, they can shape traffic from a central console and respond quickly to evolving requirements.
- SD-WAN is a bit more specific. With an SD-WAN, long-distance connections between enterprise sites, including branch offices and data centers, are made using cloud-based controls. This means that traffic can be precisely shaped, specific paths/links can be prioritized and a wide variety of connection types (including MPLS, broadband internet and even cellular) can be supported.
Both SDN and SD-WAN are important components in the emerging software-defined data center. The central idea of the SDDC is that data center infrastructure should be as flexible, responsive and cost-effective as possible. Using advanced software on top of less expensive hardware - SDN in particular is known for its synergy with commodity "white box" switches - is one way to accomplish this.
Cisco's investments in SDN and SD-WAN
At first, it looked like SDN and SD-WAN were major threats to Cisco's dominant position in networking equipment. However, the company has since rolled out several solutions that expand its huge product ecosystems into the SDN/SD-WAN world:
Cisco Application Centric Infrastructure
Cisco Application Centric Infrastructure is a unique approach to SDN that emphasizes tight integration of physical and virtual components, with a centralized management possible through the Application Policy Infrastructure Controller. A shared policy-based operating model is present across all ACI elements. Overall ACI functionality is greatly enhanced by the use of Nexus switches and Cisco fabric in the larger network.
Cisco Intelligent WAN
In March 2016, Cisco announced its Intelligent WAN Automation Services, which are built on the company's comprehensive Digital Network Architecture. DNA complements ACI by taking a similar approach across the entire corporate networking footprint, including the WAN.
In practice, Cisco IWAN greatly simplifies connectivity for branch offices. With only a few clicks, an enterprise can ensure that these remote sites are properly connected to company data centers and headquarters.
"IWAN automation eliminates configuration tasks for advanced networking features, and automatically enables Cisco best practices, application prioritization, path selection and caching to improve the user experience," explained Cisco's original announcement.
Preparing for the software-defined future
Cisco equipment will continue to be at the center of the enterprise networking picture even as groundbreaking trends such as SDN and SD-WAN evolve. With a Cisco Certified Network Associate Routing and Switching certification, you can make sure that you have the knowledge and skills to succeed in the current and future networking landscape.
