Hi all I came across this post: https://forums.whirlpool.net.au/forum-replies.cfm?t=2530363 ..and thought it might be of interest or help to many users in this mailing list. The post/thread describes an issue with Akamai's (and probably other CDN's) implementation of FastTCP (or some custom TCP stack) where TCP flow control breaks/is broken, and the receiving network or gateway is sent packets until the link is saturated and rendered unusable - effectively a DOS attack. Because of the DOS-like nature of the flood of received packets, no QoS queues or connection limiting strategies can mitigate the effect. The only current workaround is to block the offending network range, but then Akamai will just direct the client to another location. At the moment, it seems to be mainly (only?) Windows 10 updates causing the effect, so disabling updates over the internet is another temporary workaround. There is some interesting discussion in the thread above, including packet captures and observations. A couple of the posters are Mikrotik users so a Mikrotik-specific solution may well find its way there. Cheers Jeremy