SD-WAN vs. MPLS: advantages and disadvantages of the two technologies

The fundamental difference between SD-WANs and MPLS is virtualization. While SD-WAN virtualizes the network functions, MPLS technology runs on proprietary hardware. SD-WAN connections can be all types of network connections, MPLS is defined by its dedicated network connections.

MPLS advantages and disadvantages

One of the biggest advantages of MPLS is that it gets packets to their destination very reliably. MPLS offers a high quality of service when it comes to avoiding packet loss and transporting data packets from A to B with low latency. This reliability is particularly important to ensure the quality of real-time protocols such as Voice over IP (VoIP) or critical applications and to generate a high level of user satisfaction. MPLS identifies individual packets. MPLS providers are therefore able to assign a higher priority to certain network traffic. Most providers have the option of defining up to five different priority classes. This leads to clear predictability of data traffic in the network. An MPLS network is not a “best-effort” approach. You receive a clear SLA (Service-Level Agreement) for jitter, round-trip times, packet loss and downtimes and have a contact person for all components of your network.

One disadvantage of MPLS is the bandwidth costs. Users are increasingly interested in bandwidth-intensive multimedia content such as videos or cloud services. The ever-increasing bandwidth requirements often lead to high costs if a central Internet breakout with a central firewall is used and no decentralized solution is used to route Internet traffic out of the network. MPLS bandwidths are generally somewhat more expensive, although costs have fallen sharply in recent years. Another disadvantage is the inefficient use of bandwidth for main and backup solutions. These are usually configured as active/passive in the MPLS. The backup line is therefore mostly unused, but still generates costs.

SD-WAN pros and cons

SD-WAN offers several advantages over conventional MPLS networks. With SD-WAN, geographical boundaries become less important and important benefits such as transparency, scalability, performance and control of cloud services are improved.
In contrast to MPLS, there is no loss of bandwidth with SD-WAN. Multiple connections and connection technologies (MPLS, Ethernet, Internet, 5G) can be easily bundled in the underlay network. The biggest advantage of SD-WAN is the ability to cost-effectively combine and adapt network connection paths depending on the application or priority. For example, uncritical

Data traffic can be routed via a low-cost connection. In addition to decentralized access to cloud services and the prevention of network atypical traffic, the most important advantage of SD-WAN is probably security virtualization. Companies prefer network architectures that integrate security, policies and orchestration. SD-WAN security covers these bases. All devices and endpoints are fully authenticated. This aspect is becoming increasingly important in times of home office and hybrid working models.

SD-WAN vs. MPLS: it depends on you

SD-WAN offers many advantages, from cost, agility and flexibility to ease of use and deployment as well as increased security. However, networks such as MPLS will still be in demand where predictability and a clear end-to-end SLA are required or where decentralized access to clouds is not so important. This is the case for companies that have special requirements in terms of connectivity and packet delivery times. When deciding between the two solutions, companies need to weigh up the pros and cons and ask themselves which requirements are paramount in their environment. A combination of both approaches is often used.