SD-WAN with MPLS integration. Source: MEF
The SD-WAN vs. MPLS Debate
Before software-defined wide area networking (SD-WAN) came along to provide the benefits of software-defined networking (SDN) to traditionally hardware-based networking, there was Multiprotocol Label Switching (MPLS), a protocol for efficient network traffic flow between two or more locations. MPLS operates similarly to switches and routers, sitting between layers 2 and 3. (MPLS is sometimes considered layer 2.5.) It uses packet-forwarding technology and labels to make data forwarding decisions. The label is imposed between the layer 2 (data link) and layer 3 (network) headers.
Here are some of the pros and cons of each technology as we pit SD-WAN vs. MPLS in a battle of network traffic protocols.
MPLS Pros and Cons
When contemplating the “SD-WAN vs. MPLS” question, it is important to consider one of MPLS’s most important aspects: the reliable delivery of packets. MPLS generally offers excellent quality of service when it comes to avoiding packet loss and keeping a business’s most important traffic flowing. This reliability is especially essential to maintain the quality of real-time protocols, such as Voice of IP (VoIP).
MPLS reliability is possible because of the aforementioned label, which virtually isolates packets. MPLS providers can also assign a higher priority to certain network traffic. These benefits bring a sense of traffic predictability within the network. Network paths are predetermined, so packets travel only along the paths to which they’re directed.
One downside of MPLS is bandwidth cost. Today’s consumers are increasingly interested in bandwidth-hogging multimedia content such as videos and augmented reality (AR)/virtual reality (VR), and the high per-megabit cost that MPLS demands can be out of reach. Finally, an MPLS network doesn’t offer built-in data protection, and if incorrectly implemented, it can open the network to vulnerabilities.
SD-WAN Pros and Cons
Continuing the SD-WAN vs. MPLS discussion, SD-WAN offers several benefits over traditional MPLS networks. The core value proposition of SD-WAN is that it promises to dramatically impact the entire enterprise networking ecosystem. With SD-WAN, geographic boundaries are erased, and key benefits such as visibility, scalability, performance, and control are enhanced.
Unlike MPLS, SD-WAN comes with no bandwidth penalties. Customers can upgrade easily by adding new links, with no changes necessary to the infrastructure or network. Perhaps the greatest selling point for SD-WAN is the ability to cost-effectively mix and match network links according to content type or priority. Both Internet broadband and 4G LTE are less expensive than MPLS, so customers can choose those links instead of the expensive MPLS network for certain types of lower-priority traffic.
Arguably the primary advantage of SD-WAN is security. Today’s companies prefer network architectures that integrate security, policy, and orchestration, and SD-WAN covers those bases by unifying secure connectivity. In the SD-WAN architecture, a company benefits from end-to-end encryption across the entire network, including the Internet. All devices and endpoints are completely authenticated, thanks to a scalable key-exchange functionality and software-defined security.
SD-WAN vs. MPLS: It’s Up to You
The benefits of SD-WAN are hard to deny, from cost to agility/flexibility to ease of use/deployment to increased security. According to IDC, increasing numbers of service providers are adopting SD-WAN for a variety of reasons. However, private-based networking such as MPLS will always be in demand, particularly in businesses or institutions that have specific connectivity requirements. When companies ask the question “SD-WAN vs. MPLS?” they need to weigh the pros and cons and ask themselves which needs are paramount in their environment.