3 SD-WAN Challenges and Solutions
Points to consider when selecting an SD-WAN solution include WAN/LAN branch architecture, deployment and service provisioning, and centralized management.
June 14, 2022
Software-Defined Wide Area Networking (SD-WAN) uses the concept of Software Defined Networking (SDN) to distribute network traffic over a wide area network (WAN). SD-WAN automatically determines the most efficient way to route application traffic between branch offices and data centers based on pre-configured policies.
SD-WAN is managed by a central controller that sends policy information to all connected devices. The software allows network operations teams to remotely program network edge devices using zero-touch or low-touch provisioning. This minimizes, and in some cases eliminates, the need to manually configure routers in branch offices.
SD-WAN Challenges and How to Prepare for Them
Underlay Provisioning
Shifting the default SD-WAN connectivity option from a private WAN like MPLS to the Internet is logical. Most businesses have adopted a cloud-first approach for their SaaS, PaaS, and IaaS deployments. The main challenge in choosing an SD-WAN strategy is to find the most appropriate underlay service provider for an organization’s locations. Companies also need to choose between a multi-ISP or single-IP backbone strategy.
Using one IP backbone is a good option for large enterprises with global operations because it contains all traffic within a single autonomous system and keeps the jitter and latency more predictable across its applications. On the other hand, a national network does not usually care about round-trip delays, so it might consider using a multi-ISP strategy depending on specific postcodes.
However, organizations have more considerations aside from network performance. A traditional MPLS-based network operations center typically offers high focus and troubleshooting capabilities, offering end-to-end WAN circuit and edge management. An ISP is not so focused, so the vendor’s responsibility is to manage and troubleshoot connectivity problems.
Whether the IT team adopts a DIY or managed SD-WAN management strategy, it must understand the vendor’s service-level agreements (SLAs) for troubleshooting and monitoring connectivity.
Cloud Connectivity
In most cases, the IT team selecting an SD-WAN vendor requires connecting to a major cloud platform like AWS, Google Cloud, or Azure. SD-WAN vendors typically fall into one of the following categories depending on their cloud access capabilities:
Native cloud access—the vendor’s SD-WAN architecture has a built-in access capability, using the cloud’s backbone infrastructure to connect to branch sites. This option applies to vendors that use the cloud as a global backbone. Cloud gateway architecture deployments are not yet common, but they are useful if the user’s traffic final destination is to connect to the local cloud data center.
Vendor-provided access—the vendor delivers SD-WAN appliances to a cloud environment via a public gateway or private backbone. This option offers more flexibility in terms of vendor features. Public gateways and private backbones offer more efficient traffic routing than the Internet.
Customer-provided access