Merge pull request #4996 from kYc0o/br_readme

examples/gnrc_border_router: Add ethos and to
kYc0o 7 years ago
commit 998c4ab48c

@ -1,4 +1,173 @@
# gnrc_networking_border_router example
# gnrc_border_router using automatic configuration
This setup uses a single serial interface, ethos (Ethernet Over Serial)
and UHCP (micro Host Configuration Protocol).
Ethos multiplexes serial data to separate ethernet packets from shell commands.
UHCP is in charge of configuring the wireless interface prefix
and routes on the BR.
The script `` enables a *ready-to-use* BR in only one command.
## Requirements
This functionality works only on Linux machines.
Mac OSX support will be added in the future (lack of native `tap` interface).
## Setup
First, you need to compile `ethos`.
Go to `/dist/tools/ethos` and type:
make clean all
Then, you need to compile UHCP.
This tool is found in `/dist/tools/uhcp`. So, as for `ethos`:
make clean all
Afterwards, proceed to compile and flash `gnrc_border_router` to your board:
make clean all flash
## Usage
Start the `` script by doing on `dist/tools/ethos`:
sudo sh /dev/ttyACMx tap0 2001:db8::/64
This will execute the needed commands to setup a `tap` interface
and configure the BR.
Notice that this will also configure `2001:db8::/64` as a prefix.
This prefix should be announced to other motes through the wireless interface.
As said previously, `ethos` allows to send IP packets and shell commands.
This is done through the same serial interface.
By typing `help` you will get the list of available shell commands.
At this point you should be able to ping motes using their global address.
For instance, if you use the [`gnrc_networking`]( example on the mote, you can
ping it from your machine with:
> ping6 2001:db8:0:1234:0:567:8:1
Just replace this address by your mote's address.
Using `ifconfig` on the shell of your mote shows you the addresses of your
mote, for instance:
Iface 7 HWaddr: 59:72 Channel: 26 Page: 0 NID: 0x23
Long HWaddr: 5a:46:10:6e:f2:f5:d9:72
TX-Power: 0dBm State: IDLE max. Retrans.: 3 CSMA Retries: 4
Source address length: 8
Link type: wireless
inet6 addr: ff02::1/128 scope: local [multicast]
inet6 addr: fe80::5846:106e:f2f5:d972/64 scope: local
inet6 addr: ff02::1:fff5:d972/128 scope: local [multicast]
inet6 addr: 2001:db8::5846:106e:f2f5:d972/64 scope: global
inet6 addr: ff02::2/128 scope: local [multicast]
The script also sets up a ULA (Unique Local Address) address on your
Linux `tap0` network interface.
You can check your ULA on your PC with `ifconfig` Linux command.
On this example, such address can be pinged from 6lo motes:
> ping6 fd00:dead:beef::1
Thus far, IPv6 communication with between your PC and your motes is enabled.
## Issues
A known issue [#5122](
is that after ~15min global addresses on the BR Neighbour Cache dissappear.
We are investigating why it happens and we'll propose a solution soon.
If you experience it, just reboot your nodes and they will come again on-line.
# gnrc_border_router with manual config
You can use `ethos` as a standalone driver, if you want to setup the BR manually.
## Setup
To select ethos as the serial driver, be sure that the `Makefile`
has the following:
ifeq (,$(filter native,$(BOARD)))
USEMODULE += ethos gnrc_netdev2
FEATURES_REQUIRED += periph_uart
# include UHCP client
USEMODULE += gnrc_uhcpc
You'll need IPv6 access to the nodes attached to the BR from your Linux PC.
To do this, it is necessary to add a `tap` interface.
As an example, you can do it as follows:
sudo ip tuntap add tap0 mode tap user ${USER}
This will setup your `tap` interface.
Then configure it to route the packets coming from your 6lo network:
sudo ip link set tap0 up
sudo ip a a 2001:db8::1/48 dev tap0
sudo ip r d 2001:db8::/48 dev tap0
sudo ip r a 2001:db8::2 dev tap0
sudo ip r a 2001:db8::/48 via 2001:db8::2 dev tap0
Please note that the prefix `2001:db8::` is used as an example.
Then you can flash the `gnrc_border_router` example on your board:
make clean all flash
On this RIOT BR two interfaces are present.
A wired interface represents the serial link between Linux and your mote.
A wireless interface represents the 802.15.4 radio link.
In order to route packets between this two interfaces,
you can do the following:
> ifconfig 6 add 2001:db8::2/48
> ifconfig 5 add 2001:db8::3/64
> fibroute add :: via <link-local of tap> dev 6
By adding the address to the wireless interface the prefix will be
This prefix will be automatically added by the motes in the radio range.
## Usage
Run ethos by choosing a serial interface according to your board.
For instance `/dev/ttyUSB*` or `/dev/ttyACM*`.
sudo ./ethos tap0 /dev/ttyACM0
Now, you should be able to ping your nodes.
Use the global address starting by your prefix, on our case `2001:db8::`:
> ping6 2001:db8:0:1234:0:567:8:1
# gnrc_networking_border_router with SLIP
## Requirements
@ -23,6 +192,28 @@ In order to use the border router over SLIP, please check the `periph_conf.h`
of the corresponding board and look out for the `UART_NUMOF` parameter. Its
value has to be bigger than 1.
Be sure that you have replaced on your `Makefile` the lines to use SLIP.
You should have something like this:
ifeq (,$(SLIP_UART))
# set default (last available UART)
ifeq (,$(SLIP_BAUDRATE))
# set default
# Include SLIP package for IP over Serial communication
USEMODULE += gnrc_slip
## Configuration
In order to connect a RIOT 6LoWPAN border router over SLIP you run a small
@ -33,7 +224,7 @@ the program by calling something like:
cd dist/tools/tunslip
sudo ./tunslip6 affe::1/64 -t tun0 -s /dev/ttyUSB0
sudo ./tunslip6 2001:db8::1/64 -t tun0 -s /dev/ttyUSB0
Assuming that `/dev/ttyUSB0` is the device descriptor for the (additional) UART
interface of your RIOT board.
@ -41,14 +232,21 @@ interface of your RIOT board.
On the RIOT side you have to configure the SLIP interface by configuring a
corresponding IPv6 address, e.g.
ifconfig 6 add affe::2
ifconfig 6 add 2001:db8::2
and adding the SLIP interface to the neighbor cache (because Linux won't
respond to neighbor solicitations on an interface without a link-layer address)
by calling
ncache add 6 affe::1
ncache add 6 2001:db8::1
Then, to propagate the prefix you should add an address to the wireless interface:
ifconfig 5 add 2001:db8::3
After this you're basically done and should be able to ping between the border
router and the outside world (assuming that the Linux host is properly
forwarding your traffic).
@ -60,3 +258,4 @@ for further help.