Setting up the WTP

Table of Contents

1. Hardware Requirements
2. Software Requirements
3. Compilation/Configuration Process
4. Flashing the image
5. Configuring the WTP

Hardware Requirements

One or more WiFi Access Points capable of running OpenWRT 19.07 with at least one Atheros-based Wireless NIC supported by the ath9k driver.

One PC running a recent Linux distribution will is needed to build the firmware. There are no particular hardware requirements. Any reasonably recent laptop/desktop should be able to build the firmware.

The reference operating system for this guide is Ubuntu 20.04 LTS Server.

Software Requirements

These are the requirements for the machine you will use to build the firmware. Make sure to install the following packages before going ahead further.

sudo apt-get update
sudo apt-get install build-essential libncurses5-dev unzip python2.7

Compilation/Configuration Process

Clone the 5G-EmPOWER OpenWRT repository:

git clone https://github.com/5g-empower/empower-openwrt.git

This will create a directory named empower-openwrt which from now on will be referred to as $TOPDIR.

Then clone the 5G-EmPOWER config repository:

git clone https://github.com/5g-empower/empower-configs.git

This repository contains the default configuration for all the officially supported device. The officially supported devices are the ones you can find in the Pre built WTP Firmwares page.

Change into the $TOPDIR directory, update, and install all feeds:

cd $TOPDIR
./scripts/feeds update -a
./scripts/feeds install -a

5G-EmPOWER WTPs need to be connected to the Controller for all their operations. Therefore it is recommended to reserve an IP address for the Controller on the DHCP server. You can refer to the documentation of your router to learn how to reserve static IP addresses.

Then create a symbolic link to the firmware configuration you want to use:

ln -s ../empower-configs/empower-files-apu2c/ files

In this case, we are assuming you want to build a firmware for the PCEngines APU2 board. Modify the symbolic link if this is not the case. If you know what you are doing you can also modify the configuration files.

Run the configuration application:

make menuconfig

From the menu select the Target System (e.g. x86) and the Subtarget (e.g. x86_64). Then select the profile you want to build (e.g., PCEngines APU2 EmPOWER).

Save the configuration and exit, then start the compilation. If you have a multi-core machine you can increase the compilation speed by increasing the number of parallels builds with the "-j" option.

make -j 3

Flashing the image

Once the compilation is done, the compiled image can be found in the bin/ directory. For example in the case of the PCEngines APU2 platform, the image will be:

$TOPDIR/bin/targets/x86/64/openwrt-x86-64-combined-squashfs.img.gz

The method of loading the image on the wireless router (flashing) changes according to the brand/model of the wireless router. You can find the flashing instruction for all the supported models here.

Configuring the WTP

No special configuration is needed on the WTP. If everything was configured properly in the previous steps and if the WTP has IP connectivity to the controller everything should work out-of-the-box.

The default WTP configuration (defined in `/etc/config/empower) is the following:

config empower general
    option "master_ip" "192.168.100.158"
    option "master_port" "4433"
    option "network" "wan"
    option "interface" "empower0"
    list "ifname" "empower0"
    list "ifname" "empower1"

Make sure that master_ip is the IP address (not the domain name, you need to specify the IP address) of the controller. The default controller port is specified by the master_port. If you did not modify the controller configuration you do not need to modify this parameter.

However, if you need to log into the WTP you may need to make a few changes to the firewall configuration to open port 22 on the WAN interface (the Ethernet port next to the power plug).

If you attach a laptop to the second ethernet port you will receive automatically an IP address. Open a browser and point it to http://192.168.250.1.

After you log in, you can refer to the official OpenWRT wiki for information about how to open the SSH port on the WAN interface. Anyway, the web interface is pretty intuitive so it should be a big deal to navigate the various menu to find the firewall configuration tab.