Most software-defined WAN providers only offer over-the-top solutions. These SD-WANs operate over public internet connections and use VPNs to separate enterprise network traffic from public traffic.
However, there are cloud solutions partners that deliver over-the-top SD-WAN and "on-net" SD-WAN solutions as well. Unlike over-the-top solutions, on-net SD-WANs allow enterprises to operate over private MPLS connections. Which SD-WAN solution is right for your business?
How On-Net SD-WAN Solutions Work
Very few SD-WAN providers offer on-net solutions, because they lack the infrastructure required to support such technology.
Only cloud solutions partners that have their own carrier lines are capable of delivering on-net SD-WAN. The lines route data between your branch sites and cloud environment based on the policies you define in the SD-WAN's user interface.
The on-net option is slightly more expensive than over-the-top SD-WAN solutions, but it is ideal for large enterprises with high data confidentiality needs such as multinational pharmaceutical companies, government agencies, and nationwide care providers.
How Over-the-Top SD-WAN Solutions Work
Over-the-top SD-WAN solutions operate over public internet connections. The SD-WAN logically aggregates multiple internet links (DSL, cable, Wi-Fi, 4G, etc.) to establish a configurable VPN.
Since over-the-top SD-WAN utilizes multiple internet links, you may assume that such technology requires greater configuration, but that isn't necessarily the case. For example, if you set a cloud-based application's data transfer rate to 1 Gigabit per second, the solution will utilize available network resources to satisfy that parameter.
One disadvantage of over-the-top SD-WAN is that it is more prone to service disruptions than on-net alternatives, because the technology runs on unpredictable network connections. However, it is the more cost-effective option.
Over-the-Top/On-Net Hybrids
What if you want the best of both worlds? Some cloud partners provide both over-the-top and on-net hybrid SD-WAN solutions. Such technologies enable you to take advantage of the reliability and security of carrier lines as well as the affordability and convenience of public connections.
Suppose you work at a medical device manufacturing company, and you are running three applications in the cloud:
- Customer relationship management (CRM)
- Enterprise resource planning (ERP)
- Productivity suites such as Microsoft 365 (formerly Office 365) or Google Drive
Arguably, the ERP is your most valuable system due to its ability to track supply chain activity, accounts receivable, and other details related to production.
To ensure that information gets to your cloud-based ERP, it is important to utilize reliable connections. However, your cloud provider's dedicated lines may not be available near a few warehouses. To address this problem, you can configure the SD-WAN to route warehouse data across private lines when they are available and public lines when they are not.
In addition, you do not have to allocate bandwidth over private MPLS lines to transmit data from your CRM or productivity suite. For example, Microsoft Word isn't necessarily mission-critical, whereas ERP software tracks detailed financial information you can't afford to lose.
An over-the-top/on-net SD-WAN hybrid is typically the optimal choice for enterprises. Ask your cloud partner if they are able to deliver this technology.
