i dont understand how changing dns ip speeds up my sky downloads ?
Your Sky+HD or SkyQ box asks the DNS server for the IP address of the server for downloads by name. In the same way your web browser asks the DNS server for the IP for google.com or forums.thinkbroadband.com
MrSaffron's guess is that you are using Sky as your internet provider, and they have set up their DNS server to reply with the IP address of a server that is slow. (its either broken, or deliberately slow).
MrSaffron also guesses that because you change the DNS to 18.104.22.168 (which is operated by CloudFlare) when your Sky+HD or SkyQ box asks for the IP address, it is given a different IP address for a different server.
This server is faster.
If you are not using Sky as your internet provider, then talk to your internet provider.
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