SD-WAN traffic is the fastest-growing segment of the overall enterprise WAN market, increasing at a 44% compound annual growth rate, while traditional WAN will grow at only a 5% rate.
The healthy growth rate of SD-WAN is a partial vindication of the network virtualization trend. Virtual customer premise equipment (vCPE), a common element of SD-WAN, was expected to be one of the least difficult instances of virtual technology to deploy. Though it wasn’t the slam dunk everyone expected it to be, it was—to extend the metaphor—a relatively easy layup.
Indeed, operators around the world and across the spectrum are rushing to launch SD-WAN services. Verizon, AT&T and others are among those chasing the market.
While SD-WAN may be growing at a faster rate than the WAN market in general, keep in mind that SD-WAN was a barely quantifiable blip until 2015. Even if the SD-WAN becomes six times larger by 2021, as Cisco projects in its latest VNI report, it will still represent only a quarter of all WAN traffic by 2021.
And for the purpose of perspective, all WAN traffic is a sliver of overall internet traffic. All global internet traffic amounted to an average of 96 exabytes a month in 2016. All WAN traffic, meanwhile, ran at roughly 3.25 exabytes a month in 2016.
Overall traffic is heading toward 122 exabytes per month this year, and is expected to reach 278 exabytes a month by 2021. In comparison, WAN traffic is heading for about 3.75 exabytes a month this year, and could reach about 5.25 exabytes a month by 2021.
So while overall WAN traffic is growing, it’s not growing quite as fast as overall internet traffic, which means WAN will become a diminishing percentage of the total. That should be expected; the overall internet traffic rate is being juiced by the consumption of video content for entertainment, which is not a big constituent of corporate networking traffic. Again, SD-WAN is a sliver of the sliver; it might end up being a little over 1 exabyte/month by 2021.
Security issues
In its VNI report, Cisco also surveyed security professionals to find out what their biggest security concerns were. Either the security professionals surveyed have widely distributed interests, just about everything is under attack, or both.
More than half of the security pros said it was very challenging or extremely challenging to provide security for mobile devices, data in the public cloud, cloud infrastructure, user behavior (e.g., clicking on malicious links), customer data, data centers, organization data, network infrastructure, applications, and client operating systems (e.g., Windows, MacOS, etc.).
In other words, there wasn’t a single consideration in Cisco’s list of concerns where half the security pros weren’t really, really worried about security.
Last year, distributed denial of service (DDoS) attacks were—once again—off the charts. Cisco said peak attack size increased 60% year over year. In a note with the presentation accompanying Cisco’s report, the company said that the average DDoS attacks size is increasing steadily and is approaching 1.2 Gpbs, “enough to take most organizations completely offline.”
Cisco noted that DDoS attacks can represent up to 18% of a country’s total internet traffic while they’re occurring.