Combining 4G and 5G cellular services with SD-WAN can give enterprise IT pros connectivity options that are faster than wired alternatives such as MPLS and that provide benefits including rapid provisioning, improved reliability and more bandwidth for less money.\nBranch offices, which are undergoing dramatic changes in the amount of traffic they generate and where that traffic goes, can particularly benefit from 4G and 5G, and one enabler is software-defined WAN.\n\nSD-WAN combines multiple physical WAN links into one logical network and provides traffic prioritization to accelerate performance of applications that are deployed in internal data centers and in the cloud. When integrated with Wi-fi 6, SD-WAN can enable IoT, edge computing and end-to-end traffic visibility at the branch.\nChanging branch-office traffic patterns\nAs cloud services like IaaS and SaaS become the leading method for delivering applications to branch offices, more and more branches are connecting to cloud providers in addition to corporate data centers.\nWAN bandwidth demands are increasing on an average of 20% to 30% per year, and as a result SD-WAN is becoming more attractive because it enables hybrid WANs that can blend expensive wired circuits such as MPLS with less costly but also bandwidth-rich internet connections. By adding 4G LTE and 5G services to the mix, IT leaders gain wireless links that can complement, and in some cases replace, existing wired services.\n4G LTE is already in widespread use at branch locations to ensure high availability and reliability in the event of slowdowns or outages in primary wired circuits. It also provides rural sites with additional WAN options beyond DSL and T-1 circuits. As leading wireless operators compete for 5G customers, more options may emerge such as unlimited data plans that could provide branch locations with higher bandwidth at fixed costs.\n5G also promises a number of other advances including speeds greater than 1Gbps, low latency and network segmentation. Some of these features need more work before they become available, but the reality is that existing 4G and 5G networks offer performance as good as or better than many wired internet connections. Connection speeds at or above 1Gbps can meet the WAN demands of most branches, even as traffic to and from them continues to grow.\nIoT means more branch traffic\nAnother contributor to ever-increasing WAN traffic at the branch is the internet of things. IoT sensors gather enormous volumes of data, much of which needs to be turned into useful information by analytics systems based in the cloud or in enterprise data centers. Edge devices analyze some of this data locally to improve response time and reduce WAN traffic, but overall, expanding IoT use in branch offices increases WAN traffic.\n4G and 5G services in concert with in-house Wi-Fi can provide secure high-speed links from these IoT devices to the LAN to the WAN to the cloud. Such end-to-end connections can be facilitated by SD-Branch solutions, which combine SD-WAN, routing, integrated security and LAN\/Wi-Fi functions that can all be managed centrally. As SD-WAN suppliers introduce fully featured SD-Branch solutions they can offer end-to-end traffic visibility.\nWi-Fi 6 improves branch connectivity\nMost organizations will continue to rely heavily on Wi-Fi to provide connectivity not only for IoT devices, but also users and guests. Over time, they will upgrade to the latest standard, Wi-Fi 6, which provides significant improvements in terms of performance, latency, quality of service and battery life compared to previous versions. In combination with reliable highspeed, WAN links, Wi-Fi 6 will improve application performance and the ability to deploy IoT systems.\nSD-WAN and SD-Branch are becoming the standard technology to enable organizations to boost security and reliability as well as intelligently steer traffic over multiple WAN links. 4G and 5G cellular fit nicely into that architecture with links that are easy and fast to provision while providing link diversity to protect against cable cuts that can disrupt wired services. Together, they represent a game changer for branch connectivity.