Network specialists herald the software-defined wide area network (SD-WAN) as the most significant advancement in corporate networks in years.
Here’s why: SD-WAN dynamically routes traffic among multiple connections based on the performance of each link and the priority of applications using the network.
Connections may include relatively expensive, high-performance MPLS VPN links, lower-cost dedicated internet access, or cheaper, “best efforts” business broadband service. Accordingly, SD-WAN dynamically optimizes connectivity cost and application performance. (More on that here.)
Although SD-WAN is commercially available and deployment is expanding, it remains in the early stages of customer adoption. It’s no surprise, then, that prospective enterprise customers have questions about the technology itself, as well as the specifics of SD-WAN service procurement.
Specifically – what types of vendors offer SD-WAN solutions and what factors should enterprises consider when deciding which provider is the best fit for their network requirements?
SD-WAN providers loosely fall into the following four categories:
1) Established WAN equipment vendors
2) WAN solutions portfolios
3) SD-WAN specialists
4) Managed service providers
In short: not all SD-WAN vendors look the same. Established network equipment vendors like Cisco have a large, installed base of enterprise network equipment. And then there are WAN service companies like Citrix, which offer several enterprise solutions, including WAN optimization, acceleration, and firewalls, in addition to SD-WAN services.
This spectrum of SD-WAN sourcing options enables enterprises to find new suppliers to augment the WAN – or expand existing relationships – for a truly managed end-to-end solution.
SD-WAN specialists include companies like VeloCloud and Viptela, which make up a large portion of the market.
Beyond the hardware and software suppliers themselves, managed service providers such as Telstra, Level 3, and Verizon have joined the marketplace by adding SD-WAN to their WAN service portfolios via partnerships with SD-WAN suppliers.
This spectrum of SD-WAN sourcing options enables enterprises to find new suppliers to augment the WAN – or expand existing relationships with providers – for a truly managed end-to-end solution.
The core benefits associated with SD-WAN adoption are consistent across provider offerings: reduced network cost, decreased network complexity, and increased flexibility and network performance.
So how can corporate networks teams decide which SD-WAN provider best meets their network requirements? Aside from absolute price, features such as deployment model, scalability, and service package are important to consider.
The majority of SD-WAN deployment models are hardware or software-based. With equipment-based services, SD-WAN devices replace or overlay the existing router at each branch site, connecting to centralized or cloud based controllers that manage application policies and security features.
In a software-based solution, software is downloaded onto the existing router at the branch site, only requiring network access to connect and communicate with the centralized controller.
Regardless of deployment model, enterprise customers should confirm that the technology is compatible with all of the services deployed across their network and assess its ease of deployment.
While many SD-WAN services integrate easily with MPLS, Ethernet, or broadband, other transport technologies – such as legacy T-1/E-1 circuits – are not as widely supported. If WAN services from another vendor, such as WAN acceleration, are also running on the network, enterprises must verify interoperability between providers.
A network team’s tolerance for involvement and management during the deployment process is also important to consider. While some services are considered “zero touch,” with the appliance needing only power and external network access to connect, others require additional on-site training and communication with a central site during installation.
Similar to selecting a telecom service provider, the scalability and coverage of an SD-WAN provider’s solution is important to consider.
Scalability includes not only the number of individual sites a provider is equipped to handle, but also the ease with which one can add bandwidth to existing sites or new sites to the network. Some SD-WAN solutions tout upgrades that can be done overnight, compared to a few months with traditional WAN architectures. For many SD-WAN providers, scalability is only limited by the number of controllers installed in the network, with each controller able to support thousands of sites.
With only a handful of large-scale SD-WAN deployments currently in place, however, some assurance of scalability beyond historical deployments may be necessary.
Scalability includes not only the number of individual sites a provider is equipped to handle, but also the ease with which one can add bandwidth to existing sites or new sites to the network.
Finally, enterprises should seek an SD-WAN supplier that suits its procurement strategy, particularly the preference for a capex or opex based model.
Some suppliers offer upfront purchase plans for SD-WAN hardware, although they may finance the equipment to resemble an opex model. Others offer subscription-based services that spread out the cost of the technology over a multi-year contract.
For both options, customers should inquire about the cost of adding any additional software licenses or sites to the network and how that is factored into their plan. Aligning payment terms and financial strategy is a fundamental factor in this emerging market.
SD-WAN is having a profound impact on corporate WAN procurement. Although proven in initial deployments operationally and economically, the technology, supply chain, and pricing models have not yet matured. By ensuring alignment with network operation and procurement policy, SD-WAN may prove to be a lucrative enhancement to the corporate WAN.