SD WAN vs MPLS: Pros and Cons

July 26, 2018

With the increasing demand for cloud-based applications, ballooning bandwidth needs, and expanding branch offices, enterprises and service providers are reconsidering how wide area network (WAN) services should be deployed. MPLS (Multiprotocol Label Switching) and SD WAN (Software-Defined Wide Area Network) are two of most paramount technologies deployed in WAN services. This post presents the pros and cons of each technology by comparing SD WAN vs MPLS in a battle of network traffic protocols.

MPLS Basics – Hardware-Based Protocol Integrating Layer 2 and Layer 3

What Is MPLS? MPLS is a protocol for efficient network traffic flow between multiple locations. MPLS operates similarly on Ethernet switches and routers, sitting between layers 2 and layer 3 network. MPLS uses labels for fast packets forwarding and routing within a network. In MPLS network, the MPLS switch (typically Gigabit Ethernet switch and 10GB Ethernet switch) transfers data by popping off its label and sending the packet to the next switch label in the sequence. MPLS network provides customers with a method of prioritizing traffic, thus bringing a sense of traffic predictability within the network. This allows users to leverage a single network connection for multiple applications without impacting the desired performance for each of them.

As illustrated in Figure 1, time sensitive applications such as video and voice can take the highest priority while less critical applications would take the lowest priority and still function properly.

MPLS Network

Figure 1: MPLS Network Explained


 Reliable delivery of packets to maintain the quality of real-time protocols
 Using labels to isolates packets and assign a higher priority to important network traffic
 Network paths are predetermined and travel only along the paths to which they’re directed


 There is a big limitation on how long it takes to deploy
 High bandwidth cost that MPLS demands can be out of reach
 Built-in data protection is not offered

SD WAN – Software-Defined Connectivity to Cloud Platform

Data centers and enterprises are demanding more flexible, open, and cloud-based WAN technologies, rather than installing proprietary or specialized WAN technology that often involves expensive, fixed circuits, or proprietary hardware. Based on this point, SD WAN is developed and widely applied in WAN connections. SD WAN is extremely appropriate to connect branch offices to a central corporate network, or to connect data centers separated by geographic distances. With SD WAN, geographic boundaries are erased, and you can enable communications with all network endpoints. It simplifies the management with zero-touch deployment and reduces recurring network costs.

In the SD WAN architecture, a company can benefit from end-to-end encryption across the entire network, including the wireless WAN, the Internet as well as the private MPLS. All devices and endpoints are completely authenticated thanks to the scalable key-exchange functionality and software-defined security from cloud services in the SD WAN architecture.

sd wan

Figure 2: SD WAN Network Application


 Removing expensive routing hardware and avoiding vendor lock-in
 Erasing geographic boundaries and provisioning connectivity and services from the cloud
 Reducing the costs of WAN connectivity costs by leveraging lower-cost services
 Speeding service agility with increased performance
 Built-in WAN optimization and security
 Flexible and upgrade easily (no bandwidth penalties)
 Network visibility


 There’s a possibility of jitter and packet loss

Customer Focus: Cost, Reliability and Security

After looking through the pros and cons of SD WAN and MPLS, the differences between SD WAN vs MPLS might be much clearer. When contemplating the SD WAN vs MPLS question, cost, reliability and security are the three most imperative focuses among customers we came across.


One of the biggest challenges for enterprises today is managing their WAN costs. As aforementioned, the legacy MPLS networks have been proven to be very expensive, and the emerging alternatives SD WAN presents compelling price as well as performance benefits. Since MPLS network contains bandwidth-hogging multimedia content such as videos and augmented reality (AR)/virtual reality (VR), the high per-megabit cost that MPLS demands can be out of reach.


Another main point customers focus on is the reliability of the traffic flowing for businesses. The main goal of SD WAN technology is to deliver a business-class, secure, and simple cloud-enabled WAN connection with as much open and software-based technology as possible. While for MPLS technology, the reliable delivery of packets is most appealing among IT technician. MPLS generally offers excellent quality of service when it comes to avoiding packet loss. This reliability is especially essential to maintain the quality of real-time appliances, such as VoIP phones, video conferencing or remote desktops.


Many of today’s companies prefer network architectures that integrate security, policy, and orchestration, and SD WAN covers all these bases by unifying secure connectivity. Modern SD WAN provides a way to connect the WAN directly to the cloud across optimized links with improved flexibility and security, which can not be comparable with MPLS.


SD WAN vs MPLS, who is the winner? When asking this question, you need to weigh the pros and cons and decide which needs are paramount in the environment. With all the benefits offered by SD WAN technology, it’s likely that most enterprises and service providers prefer the more cost-effective SD WAN. The merits of SD WAN are hard to deny, from cost to agility/flexibility to ease of deployment, and to the increased security. SD WAN adoption is seeing remarkable growth as more and more businesses are seeking to streamline their WAN infrastructure and evolve toward more cloud-based applications. However, MPLS might still trump SD WAN if your company had a lot of mission-critical or real-time applications running over the WAN.


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