@Magga 

Hello, thanks for asking.

As per your description, it seems that the upload speed is not good and no more than 15mb when your computer in the bedroom is connected to the tenda dual band ac1200 router, am I right?

If this is the case, I may need to clarify what is a mesh network. A mesh network is simply a set of devices that extends the range of the Wi-Fi signal. E.g. a part of the house may be too far away from the Wi-Fi source to send/receive the radio signals, then the mesh nodes just add extra Wi-Fi access points in a different place and they relay all the signals back to the main one.

The internet speed, however, is dependent on more than just your Wi-Fi. It is the connection to your ISP or internet source. As well as their connection through to whatever relay onto an internet backbone cable. The mesh network or booster will make your signal stronger, but will not necessarily make your connection faster.

Hope this makes sense but let me know if you have other opinions. Thanks.