From Pi My Life Up:
A Raspberry Pi WiFi Extender is a cheap and power efficient way of increasing the total range of your WiFi Network. A WiFi extender differs a fair bit from a WiFi access point.
The main difference being that instead of getting its network connection from Ethernet, it instead gets its network connection from a WiFi adapter.
For this reason, to complete this tutorial you will require two WiFi adapters, one of these must be access point capable.
You will face a fair bit of degradation in the speed of your network connection when connecting to the Wi-Fi repeater. The main reason for this is that you must wait for the traffic to go over your initial Wi-Fi connection then be repeated from your Raspberry Pi for devices to connect to.
This tutorial can be combined well with our VPN Access Point tutorial, you can find the tutorial on how to set that up located directly after this tutorial. Basically, it will show how to setup a OpenVPN client and redirect all traffic through that client.
Please note however, this tutorial will require some slight changes, we will explain those changes needed at the end of this tutorial.
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