There has been plenty of hype around secure access service edge. Some even say it is replacing legacy network and security architectures. Drew Robb, writing for TechRepublic Premium, lays out what it is, how it fits within the security and networking landscape, whether it is replacing SD-WAN, its benefits, its challenges, and how to implement it.

Dell'Oro Group analysis shows that the SASE market is booming. It has experienced revenue growth of 20% or more for 17 consecutive quarters. The global SASE market, combining SD-WAN and SSE technologies, is worth around $10 billion annually.

Some believe that SASE will quickly gobble up the entire SD-WAN marketplace. Certainly, SASE combines the cloud-delivered security services of SSE with the networking capabilities of the SD-WAN. As well as enhancing traditional SD-WAN capabilities, SASE adds centrally controlled, Internet-based networks with built-in networking and security-processing capabilities that are fully integrated with all the different SSE elements. Long-term, SASE will overwhelm SD-WAN. But Dell'Oro still expects SD-WANs to rack up $6 billion in sales by 2027. By that time, SASE revenue will be almost double.

Thus, the SD-WAN will suffer a slow but steady decline. But the rumors of its demise are greatly exaggerated. Single-purpose SD-WANs are destined to enjoy reasonably good sales numbers for the next few years at least. After that, SASE suites will assume most of the SD-WAN duties. Those functions remain critical to extending connectivity beyond an organization's internal network for secure network access by its remote users. SD-WANs, for example, have the ability to optimize connectivity to cloud services such as Amazon Web Services or Microsoft Azure.

SD-WAN innovation isn't finished either. The latest tools include features such as dynamic path selection, self-healing wide-area networking capabilities, and a more consistent application and user experience. They can also support high-bandwidth applications, such as voice or video.