This page contains information about using Linux for Vehicle-to-X communication, also known as Intelligent Transportation Systems or IEEE 802.11p.


Bernd Lehmann will talk at 32nd Chaos Communication Congress (32C3) about Vehicle2Vehicle Communication based on IEEE 802.11p.
Patches for supporting 5.9 GHz band posted.
Patch adding OCB mode support to ath9k driver will appear in Linux 4.4.


Linux kernel

Mainline Linux kernel 3.19 contains most of the changes needed for 802.11p support. The only missing part is the patch for ath9k driver, which needs to be fetched from our repository.

Clone the repository (this will take a few minutes)

git clone --branch its-g5_v3
cd 802.11p-linux

Install needed packages if you haven’t them already

sudo apt-get install gcc libncurses5-dev make

Prepare the folder for compilation

mkdir _build

Use the appropriate defconfig

make O=_build x86_64_defconfig

Configure the kernel if necessary (enable ATH_9K, MAC80211_OCB_DEBUG, CONFIG_MAC80211_STA_DEBUG etc.)

cd _build
make menuconfig

Run the compilation

make -j4

Install the modules and the kernel

sudo make modules_install
sudo make install

iw – wireless configuration tool

IEEE802.11p support is available in iw 4.0 and later. If your system has an older version follow this procedure.

Install pkg-config and libnl development files

sudo apt-get install pkg-config libnl-genl-3-dev

Clone the official iw repository

git clone git://
cd iw

Build it


Install it

sudo PREFIX=/ make install

Test it

/sbin/iw | grep -i ocb
 	dev <devname> ocb leave
 	dev <devname> ocb join <freq in MHz> <5MHZ|10MHZ> [fixed-freq]

wireless-regdb – regulatory information

Install the needed dependencies

sudo apt-get install python-m2crypto

Clone the repository, compile it, install it

git clone --branch its-g5_v1
cd 802.11p-wireless-regdb
sudo make install PREFIX=/

CRDA – Central Regulatory Domain Agent

Install some extra packages

sudo apt-get install python-m2crypto libgcrypt11-dev

Clone the repository

git clone --branch its-g5_v1
cd 802.11p-crda

Copy your public key (installed by wireless-regdb, see above) to CRDA sources

cp /lib/crda/pubkeys/$ pubkeys/

Compile and install CRDA (custom REG_BIN is needed on Debian)

make REG_BIN=/lib/crda/regulatory.bin
sudo make install PREFIX=/ REG_BIN=/lib/crda/regulatory.bin

Test CRDA and the generated regulatory.bin

sudo /sbin/regdbdump /lib/crda/regulatory.bin | grep -i ocb
country 00: invalid
 	(5850.000 - 5925.000 @ 20.000), (20.00), NO-CCK, OCB-ONLY

Now is the right time to reboot the computer into the newly compiled kernel.

Configuring a wireless interface for OCB mode

sudo iw reg set DE
sudo ip link set wlan0 down
sudo iw dev wlan0 set type ocb
sudo ip link set wlan0 up
sudo iw dev wlan0 ocb join 5890 10MHZ

Get the interface statistics

ip -s link show dev wlan0