Microsoft announced at Ignite that the first 5 networking providers, globally, have been certified to deliver Office 365 networking "in a way that minimises latency and maximises performance and reliability of enterprise connectivity on Office 365 user experience". This is critical because, according to Microsoft's post linked above, "the most significant factor that determines the quality of the Office 365 end user experience is network reliability..."
4 of the 5 Office 365 Preferred Networking Partners are very large, long-time Microsoft partners (Citrix, Zscaler, Silver Peak and NTT). The fifth partner, NetFoundry, is a NaaS (Network-as-a-Service), Zero Trust networking startup.
According to Microsoft's post linked above, all 5 of the partners "have met Microsoft’s testing requirements" and "support a high-quality end user experience." Microsoft also stated that Cisco, Oracle and Riverbed are in the midst of trying to get qualified.
NetFoundry's O365 networking optimisation solution states that it is the only one of the 5 Preferred Partners to both enable the lowest latency Office 365 networking (direct Internet without trombone through third party cloud infrastructure), and not require a specific WAN solution, instead functioning as software-only NaaS, on top of any WAN. The same NetFoundry Platform used for O365 optimisation also enables Zero Trust, private Azure connectivity, and has both NaaS and Developer Platform options.
Galeal Zino, CEO of NetFoundry, stated "We are excited to be the first Zero Trust, NaaS provider to be a certified partner in the Microsoft Network Partner Program for Office 365. We are 'the easy button' for optimised O365 because our solution enables businesses to optimise O365, without implementing an SD-WAN solution or deploying hardware, while securing business sites with our Zero Trust solution, and without needing to send the data through third-party infrastructure."